TOEFL® Word List

Definition: A large volcanic crater, typically one formed by a major eruption leading to the collapse of the mouth of the volcano.

Example senences:

• The sequential development of multiple summit calderas of shield volcanoes gives clues about how the spatial location of shallow magma chambers evolves with time and how the magma supply into these chambers evolves

Camouflage is the way in which some animals are colored and shaped so that they cannot easily be seen in their natural surroundings. For example:

• The distinctive black and white coloring of jackass penguins is a form of camouflage.
• Underwater predators looking up only see white, and predators looking down only see black.
• Many sea animals have, over time, developed different kinds of camouflage to help them blend in with their environment and avoid detection by predators.
• Sloths live high in the canopy, feeding on a wide variety of leaves and fruits. Green algae grow in the sloths’ fur, which enables it to remain camouflaged from predators. 

Definition: (in singular) The uppermost branches of the trees in a forest, forming a more or less continuous layer of foliage

Example sentences:

• The American chestnut did not really disappear from the eastern forests-it ceased to be a part of the forest canopy and is now a part of the shrub understory.

Definition: An economic and political system in which a country’s trade and industry are controlled by private owners for profit, rather than by the state.

Example sentences:

• Under capitalism all profit is ultimately the result of the exploitation of the workers

The adjective captivating describes something that holds your attention. You might find a marathon of episodes of a TV show so captivating that you forget to eat dinner. When people are captivating, they're often very intelligent, attractive, charming, or otherwise fascinating. Something that catches and holds your interest is captivating, like a captivating mystery novel you just can't put down.

Take a look at its use below:

• A captivating story
• A captivating smile
• The story is captivating and keeps the viewer hooked.
• Our university is looking to hire captivating teachers that can keep students engaged for long periods of time.

Your carbon footprint is the sum of all emissions of greenhouse gases like CO2 (carbon dioxide), which were induced by your activities in a given time frame. Usually a carbon footprint is calculated for the time period of a year.

Definition: Relating to the heart and blood vessels:

Example sentences:

• Uncontrolled diabetes increases the risk of cardiovascular diseases such as heart attack and stroke.

Definition: A substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change

Example senences:

• Chlorine acts as a catalyst promoting the breakdown of ozone

A cause is something that leads to something else, the thing it leads to is called effect. That’s why you're likely to hear the phrase "cause and effect" when people are trying to analyze how things happen. The following patterns and expressions are commonly used with the noun “cause”. Note that A is the cause. B is the result.

• The/one cause of  B is A .
• A is one/a cause of  B.
• Another cause of B  is A.

Here are example sentences:

• One primary cause of overpopulation is the higher birth rate.
• The leading cause of overpopulation is the higher birth rate.
• The underlying cause of youth violence is poor social attachments from earliest childhood.
• The ecological footprint is one primary cause of global warming.
• The ecological footprint is one major cause of global warming.
• Another major cause of global warming is the increasing concentrations of ozone-depleting chemicals
• Another main cause of global warming is emissions of greenhouse gases.

As you can see from the examples, adjectives such as "primary", "main", "major", "leading", "underlying" are often used with the noun ‘cause’.  

The meaning of "underlying" here refers to something beneath something else. But the word carries a more subtle meaning. We use the word ‘underlying’ to describe something hidden but still important, something that is the basic or root cause of something. Therefore, when we say “A is an underlying cause of B”, it means ‘A is the root cause of B’. For example,

• A lack of educational opportunity is an underlying cause of poverty.  

The word cause can also be a verb. The verb “to cause” means “to produce an effect”, like when you slice onions and it causes your eyes to water. The past tense of “cause” is “caused”, as used in the sentence “What caused you to lose your job?”  In this sentence, someone wants to know the reason the other person lost their job (which is the effect.)

The patterns often used with the verb “cause” are the following.

• A cause(s) B
• A cause(s) B to + Verb
• B is caused by A

Here are examples for each of the patterns:

• The increasing popularity of ebooks causes a decline in paper book sales.
• The increasing popularity of ebooks causes the sales of paper book to decline.
• The decline in paper book sales is caused by the increasing popularity of ebooks.

Definition: well-known and popular

Example sentences:

• San Francisco is celebrated for its multicultural makeup.

Definition: An insoluble substance which is the main constituent of plant cell walls and of vegetable fibres such as cotton. It is a polysaccharide consisting of chains of glucose monomers

Example sentences:

• Major constituents of the cell wall are cellulose, hemicelluloses and pectins.

Definition: A marine mammal of the order Cetacea; a whale, dolphin, or porpoise

Example sentences:

• Killer whales also prey on mammals such as other cetaceans and pinnipeds, as well as on birds and large fish.

Definition: Typical of a particular person, place, or thing;A feature or quality belonging typically to a person, place, or thing and serving to identify them

Example senences:

• Dishes in each region have their own set of characteristic flavours.

Definition: Filled with excitement, tension, or emotion:

Example sentences:

• Even though I've read the book three times so far, never once have the words conveyed the sense of excitement and the charged atmosphere that came across on film.

Definition: An infectious disease causing a mild fever and a rash of itchy inflamed pimples which turn to blisters and then loose scabs. It is caused by the herpes zoster virus and mainly affects children.

Example sentences:

• Generally, chickenpox is a milder illness for children than it is for adults.

Chlorophyll is a green substance in plants which enables them to use the energy from sunlight in order to grow.

Example sentences:

• Chlorophyll is located in a plant’s chloroplasts, which are tiny structures in a plant’s cells. This is where photosynthesis takes place. Phytoplankton, the microscopic floating plants that form the basis of the entire marine food web, contain chlorophyll, which is why high phytoplankton concentrations can make water look green.

Definition: (Of an illness) persisting for a long time or constantly recurring

Example sentences:

• People with chronic respiratory or cardiovascular illness or immune system diseases are also more susceptible than others to pollutants.

Definition: (Of biological processes) recurring naturally on a twenty-four-hour cycle, even in the absence of light fluctuations

Example sentences:

• Although caffeine's effects on alertness and sleep are well known, researchers weren't sure how it affects the circadian clock in humans.

Definition: Find a way around (an obstacle):

Example sentences:

• Clever strategists that we were, we decided to circumvent this problem or objection by presenting a symposium rather than submitting independent papers.

Definition: make clear and (more) comprehensible

Example sentences:

• If you have doubts while reading the catalog, make sure to email your major adviser to clarify your confusion.

Definition: of textures that are rough to the touch or substances consisting of relatively large particles

Example sentences:

• Process the nuts until they're ground to coarse meal, then continue until you finally get a smooth paste.
• The movie contains some disturbing violence, coarse language, drug use and sexual content.

Definition: A silky case spun by the larvae of many insects for protection as pupae

Example sentences:

• I saw a spider's web and an insect larva beginning to spin a cocoon.

If it's related to thinking, it's considered cognitive. A child's cognitive development is the growth in his or her ability to think and solve problems. Used in a sentence, “Her cognitive style was much different from my son’s.” or, in other words, her thinking style was much different, or the way that they came to the same answer could have been very different. 

Cognitivity refers to the adjective form of the word and is the state of thinking.

Example sentences:

• As children grow older, their cognitive processes become sharper.
• Estrogen is said to enhance cognitive function.
• I had an aneurysm and my speech was not badly affected, but the singing has really helped to improve my cognitivity and get my confidence back.

Definition: well reasoned; ideas that are clearly presented.

Example sentences:

• The party’s policies were based on prejudice rather than on any coherent ideology.
• When we first hear a song, it stimulates our auditory cortex and we convert the rhythms, melodies, and harmonies into a coherent whole.

Definition: (Of a structure) fall down or in; give way

Example sentences:

• The structure suddenly collapsed, sending lecturer and papers sprawling.

Definition: An instance of one moving object or person striking violently against another:

Example sentences:

• Three people have died in a head-on collision between two cars in a weekend which also saw two police officers seriously injured in a separate road accident.

Colonial means relating to countries that are colonies, or to colonialism. Example sentence:

• The colonial period occurred when America was still under British rule, so any time before 1776. This is because the British people were people who came to settle in a new land.

Definition:

Example sentences:

• Quite soon, however, the invader's aims broadened into conquest and colonization on an unprecedented scale.

"Colony" can have two meanings. The first is that it is a place where a group of people with the same interest or occupation are gathered. It can also be a group of organisms of the same type living or growing together. If you have more than one colony, you change the word to colonies, with i-e-s. Let’s check out some examples:

• By 1650, England had established a dominant presence on the Atlantic coast. The first colony was founded at Jamestown, Virginia, in 1607. 
• America was broken up into thirteen colonies when the British first came over from England.
• Often a polyp produced by sexual reproduction initiates growth of a colony asexually by budding. Budding occurs when a portion of the parent polyp pinches off to form a new individual.

The verb combust basically has the same meaning of the verb “burn”, and the noun ‘combustion’ basically means “burning”. We use it a lot when we talk about the burning process in car engines and power plants.

• Since fuels require oxygen to combust, reduced oxygen content in the vapor space lowers the risk of unwanted combustion.

• Natural gas is frequently combusted in gas turbines as well as boilers.

• Oxygen, carbon dioxide, and carbon monoxide are all indicators of the efficiency of the combustion process.

“Combustible” can be an adjective or a noun. Used as an adjective, it describes something that can be burned easily. For example:

• The fuel is highly combustible.

Used as a noun, it refers to something that can be burned easily. For example

• Combustibles such as coal and gasoline are easy to burn.

Definition: be perceived in a certain way; make a certain impression; to find or discover usually by chance or mistake

Example sentences:

• She comes across as someone who’s less interested in expressing herself artistically, and more interested in simply getting famous.
• Those career centers should talk more frequently with actual employers, because in reality it comes across as pushy and overbearing.

When something is common, it means something is done by many people or occurs or appears frequently. Here are example sentences:

• In some countries, it is quite common for teenagers to have a job. 
• One of the most common uses of computers has been for quick and easy communication.

Common can also mean belonging to or shared by two or more people or groups. Here are example sentences:

• They have a common ancestor.

The following phrases with the word 'common' are often used:

• a common sight
• It is common practice for someone to do something
• in common
• is common to

Here are examples:

• Buffalo were once a common sight on the American plains.
• It is common practice for some students to take a gap year between high school and university in order to do charitable work abroad in underdeveloped countries
• The two cultures have a lot in common.
• The problem is common to laptop computers. = It's common for laptop computers to have this problem.

Definition: in a relative manner; by comparison to something else

Example sentences:

• Sesame Street was already a quality show, and its dependence on government subsidies has been comparatively small for years.

Definition: The action or fact of complying with a wish or command:

Example sentences:

• On Friday, police offices called 100 police officers to patrol the streets and enforce compliance with the social distancing rules.

• The government needs to penalize companies that are not in compliance with labor laws.

• All personal data collected is processed in compliance with current legislation and, in any case, with the utmost confidentiality.

• Our company has always acted in compliance with environmental laws.

Definition: The nature of something’s ingredients or constituents; the way in which a whole or mixture is made up

Example senences:

• The sensitive camera will be able to precisely measure the planet's temperature and chemical composition, which will allow for computer models of the atmosphere and climate to become much more exact.

Definition: prevent from being seen or discovered

Example sentences:

• Over the past few years, He have been creating fake companies to conceal the fraudulent checks.

Conceivably means in a conceivable manner or something may be conceived/possible. Conceivably is the adverb form of the verb “conceive”.

Example sentences using the word “conceivably”:

• Conceivably, the date could be moved up a week.
• We could conceivably (meaning possibly] finish tomorrow.

Definition: A small musical instrument played by stretching and squeezing a central bellows between the hands to blow air over reeds, each note being sounded by a button.

Example sentences:

• All varieties of accordion (including the concertina and the bandoneon) have been made in both double and single-action models.

Definition: be in accord; be in agreement; happen simultaneously

Example senences:

• The official said the prime minister concurred with White House assertions “that this has nothing to do with the Iran deal.”
• Let’s hope your friend is able to see this chat, and that she will concur that $50 a year is a small price to pay.

Definition: Organize and carry out;Transmit (a form of energy such as heat or electricity) by conduction

Example sentences:

• Organize and carry out: He said that it was intended to conduct a survey and carry out improvements in consultation with residents.
• Copper conducts heat and electricity extremely efficiently and is less expensive at the present.
• Conduct an experiment.

The word conform means following or complying with the rules or law. Someone who usually agrees without giving trouble is a conformist. The word can mean to agree or obey. It is sometimes used with the prepositions to or with minus an object.

Example sentences:

• The animals' behavior conforms to a common pattern.
• Our budget numbers conform with official estimates.
• The building doesn't conform to local regulations.
• She refuses to conform to society's traditional image of a mother.
• Employees have to conform with company rules.
• Citizens should conform to the laws of the land.

Conform is also used to describe the act to do what other people do or to behave in a way that is accepted by most people. Look at the example below:

• Most teenagers feel pressure to conform.

Definition: The state of being congested:

Example sentences:

• The bus lanes are designed to ease traffic congestion but they remain controversial.

A congregation is a group of people or animals staying together.

Penguins congregate in groups to stay warm. With their group congregations, they are able to reproduce their offspring in extremely cold temperatures.

Definition: A person who conquers a place or people

Example sentences:

• Until 1773, at about the time the Spanish conquerors arrived, Antigua had been the capital of Guatemala

Definition: Aware of and responding to one’s surroundings;Having knowledge of something

Example sentences:

• Although I was in pain, I was conscious. The pupils were aware of the obesity problem and conscious of the need to eat healthy foods.

Definition: The action of conserving something, in particular: preservation of the natural environment and of wildlife or prevention of wasteful use of a resource

Example senences:

• Broader efforts to cut back sprawl and promote energy conservation are just as important as personal economies.

Definition: Prevent the wasteful overuse of (a resource):

Example senences:

• Industry should conserve more water

Definition: Be composed or made up of

Example sentences:

Definition: obvious to the eye or mind

Example sentences:

• In the deep sea, where light is dim and blue, animals with bigger eyes see better—but bigger eyes are more conspicuous to predators

Definition: A group of stars forming a recognizable pattern that is traditionally named after its apparent form or identified with a mythological figure. Modern astronomers divide the sky into eighty-eight constellations with defined boundaries.

Example sentences:

• Maria and her father lay out under the stars, naming the constellations.

Consume can mean to eat or drink (something). Here are example sentences:

• The dogs consume (meaning eat) a bag of dog food each week.
• It's become accepted wisdom that wine consumed with a meal is healthier than wine consumed on an empty stomach. 
• Fat tends to be considered bad for us because it is often associated with weight gain and high blood cholesterol levels. However, certain types of fat give protective benefits to the heart if consumed in moderation.

Consume can mean to use (fuel, time, resources, etc). Here are example sentences:

• The new lights consume less electricity.
• Though hybrid cars consume less fuel than conventional cars and are now growing in popularity, there is still an issue regarding the environmental damage of the hybrid car battery.

Consumption means using, buying or eating something. Here are example sentences:

• The doctor recommended that she reduce her consumption of sugar. 
• Excessive alcohol consumption can cause major health problems.
• Excessive consumption of soft drinks in childhood has been shown to lead to calcium deficiency and more broken bones.
• The daily consumption of red meat should be no more than 80 grams.

Let’s look at some other meanings of the word “consumption” and how it can be used in sentences:

First meaning - the use of something (such as fuel). Here are some example sentences:

• The world's energy consumption is expected to increase considerably as a result of population growth (electricity consumption = the consumption of electricity)
• The jet's high fuel consumption makes it expensive to operate.
• If we don't reduce our energy consumption, we will run out of fuel. 

Second meaning - use by a particular group of people

Here is an example sentence:

• The governor said that the report was not for public consumption ( This means it was not meant to be seen by the general public; it was intended only for a few people.)

One interesting phrase you can learn is "not fit for human consumption". When something is "not fit for human consumption" it means you risk getting sick, or even dying, if you eat or drink it. Here is an example:

• This food is not fit for human consumption. [=not fit to be eaten by people]

Another term we often heard is "Conspicuous consumption". Conspicuous consumption is buying something to show off. Here is an example sentence:

• A classic example of conspicuous consumption is buying a thousand-dollar smartphone.

The verb "contaminate" has the same meaning of the verb "pollute". However, ‘contaminate’ can also be used in areas where ‘pollute’ does not work. That’s mostly the case when we talk about microbiology and organisms in general, as in this example:

• Be careful not to allow bacteria to contaminate the wound.
• Don't touch the microchip or the oil on your hands will contaminate it.

Additionally, contaminate is more frequently used for pollution related to nuclear energy. For instance:

• Nuclear weapons plants across the country are heavily contaminated with toxic wastes.

Definition: Causing or likely to cause an argument; controversial:

Example sentences:

• The most contentious issue is likely to be a provision encouraging commissioners to facilitate voluntary co-operation by witness to be heard in private.

Continental is used to refer to something that belongs to or relates to a continent. Here are example sentences:

• The most ancient parts of the continental crust are 4000 million years old.
• Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. Tectonic plates have two primary types: oceanic plates and continental plates. 

To contribute is to give (something like money or time) in order to help achieve or provide something. Here are examples

• He contributed (means donated) 100 dollars to the charity.
• The volunteers contributed their time towards cleaning up the city.

The phrase "contribute to" can mean "cause". Here are example sentences: 

• Heavy drinking contributed to her death. (This means heavy drinking helped to cause her death).
• Carbon dioxide significantly contributes to global warming.

The phrase "contribute to" can also mean "to give something or to help make something happen"

• He did not contribute to the project.
• Many players have contributed to the team's success.

When you make a contribution, it means you're giving something away — whether it's your money, your possessions, or your time. A contribution can take many forms. Some contributions are measurable, like a $10 donation to the Salvation Army. Others are less tangible.

Here are more examples using “make a contribution”:

• She made a 100-dollar contribution (This means to make a donation) to breast cancer research.
• He made an important contribution to the debate.
• I made a significant contribution to your group’s project.
• They want to make a monetary contribution to the building of the new stadium.
•  As mayor, he made many positive contributions to the growth of the city.

·       

When you contrive, you make a plan or a plot. Even though contrive often has a false or cunning feel to it, it is not always a bad thing. Mental effort is always required though, as contrive is often used in connection with inventing schemes and plans to make something happen.

Example sentences:

• The prisoners contrived a way to escape.
• Native Americans contrived [=designed] weapons out of stone, wood, and bone.

Conventional is an adjective for things that are normal, ordinary, and following the accepted way.This word describes what is typical and ordinary and that which follows accepted standards of behavior or taste. Here are examples

• The wedding was very conventional, there were no big surprises.
• I’m looking for a conventional private school for my son to attend.

One term you will often hear is 'conventional wisdom'. The conventional wisdom is a generally accepted theory or belief.  Here is an example sentence:

• For a long time, conventional wisdom said that we should drink eight glasses a day.

Definition: to communicate; to make something known to others

Example sentences:

• It is extremely rare for a government to refuse publicly to accept an ambassador, meaning that most rejections are conveyed privately.
• A logo should immediately convey a company’s identity.

Definition: A hard stony substance secreted by certain marine coelenterates as an external skeleton, typically forming large reefs in warm seas

Example sentences:

• The rest of the island is characterized by beautiful sandy beaches, coral reefs, warm clear blue waters and idyllic islands.

Definition: Similar in character, form, or function:

Example sentences:

• We discussed our corresponding viewpoints

Stronger acids with a lower ph values are corrosive. This means they can attack metals and destroy skin if spilled.

Definition: Act against (something) in order to reduce its force or neutralize it

Example sentences:

• Unequally spaced white stripes painted across the road leading up to an off-ramp have been used to create an illusion that counteracts motion adaptation and reduces driving speed.

Definition: A person or thing holding a position or performing a function that corresponds to that of another person or thing in another place

Example sentences:

• The clothes the actresses wear are noticeably different from their Western counterparts.

Definition: A qualification, achievement, personal quality, or aspect of a person’s background, typically when used to indicate that they are suitable for something:

Example sentences:

• He had stellar academic credentials, a tremendous background, had succeeded at everything he had done.

Definition: Of, relating to, or denoting the last period of the Mesozoic era, between the Jurassic and Tertiary periods

Example sentences:

• The Jurassic and Cretaceous together were the age of giant reptiles.

Definition: A narrow opening or fissure, especially in a rock or wall

Example sentences:

• Many creatures hide in crevices in the rock.

To critique means to exam or review critically. Many times, when a critique visits a restaurant, the entire staff gets very nervous, and wants everything to go perfect. This is because they know they they will be reviewed and “critiqued” over every last detail. You can think of critique as reviewing, but in a harsher manner.

• I think that the movie critique was too harsh, I loved the movie he said was garbage!

Definition: A large predatory semiaquatic reptile of an order that comprises the crocodiles, alligators, caimans, and gharial

Example sentences:

• In other species, such as monitor lizards and crocodilians, the lungs are partitioned into chambers made up of an intricate net of support structures

Cross-pollination refers to the transfer of pollen from the male reproductive organ (an anther or a male cone) of one plant to the female reproductive organ (a stigma or a female cone) of another plant.

Example sentences:

• Insects and wind are the main agents of cross-pollination.

• Sometimes cross pollinating is used intentionally in the garden to create new varieties. For example, a popular hobby is to cross pollinate tomato varieties to attempt to create new, better varieties

The Earth's crust is its outer layer. Example sentence:

• The continental crust is thought to have originated from the movement of magma when plate tectonics first formed billions of years ago.
• The Earth consists of three main layers: the core, or the inner layer; the mantle, in the middle; and the crust, which includes the continents and ocean floor. 

A crust is a hard layer of something, especially on top of a softeror wetter substance. Example sentence:

• As the water evaporates, a crust of salt is left on the surface of the soil. 

Definition: Adjective (crust)

Example sentences:

• Throughout the world, most of the earthquake activities are confined to plate margin associated with crustal deformation.
• Glaciation and crustal activity have given the island its unique shape.
• At the bottom of the Pacific Ocean is a daisy chain of volcanoes, faults and crustal fractures.

When you want to talk about something that causes something bad to happen, we often use the word “culprit” instead of “cause”

For example.

• Ultraviolet A rays are often the real culprit for health problems related to too much sun exposure.
• A banana left on the steps can be a culprit for making you slip and fall.

If you cultivate land or crops, you prepare land and grow crops on it. Cultivation is the act of cultivating.The adjective cultivable describe land that can be cultivated.

Here are example sentences

• It is believed that due to climate change, people moved from animal hunting to gathering and agriculture. About 10,000 years ago, some human groups began to raise animals and cultivate domesticated plants.
• Prehistoric peoples settled the area and began to cultivate the land.
• Some of the fields are cultivated while others lie fallow.
• The burning of woodland created an open clearing for the cultivation of hazel trees and grazing animals.  
• In the past cultivation of crops was a labor-intensive process.
• Arid land is unsuitable for many crops and must be irrigated in order for cultivation to take place.
• Cultivable land can be used to grow crops.
• Most of the island isn't cultivable - the soil is too rocky.

Definition: Restrain.

Example sentences:

• Worries over job security will curb consumer spending.

If something has been done a certain way for a long time and has become generally accepted, it's a custom.  You can think of a custom being the same thing as a tradition.​ Here are examples:

• It is custom for Americans to eat turkey on Thanksgiving.
• It is custom for Koreans to make songpyeon on Chuseok.

Definition: The standared of

Example sentences:

• The high caliber of his work earned him a raise in pay

Definition: Relating to or resembling a dog or dogs

Example sentences:

Definition: A deep gorge, typically one with a river flowing through it.

Example senences:

• The most familiar type of canyon is probably the river canyon. The water pressure of a river can cut deep into a river bed.

Definition:

Example sentences:

• It diverts the attention from real social issues only to, in turn, accommodate vile capitalistic policies.

Definition: CO2

Example senences:

• Plants give out oxygen and animals expel carbon dioxide and methane.

Definition: A salt of the anion CO32-, typically formed by reaction of carbon dioxide with bases.

Example sentences:

• The reaction with carbonates gives the nitrate salt, water, and carbon dioxide. In natural water systems, many common minerals are formed by anion substitution-precipitation reactions, among them carbonates, phosphates, and the sulfate-containing rocks.

A carnivore is an animal that gets food from killing and eating other animals. Carnivores generally eat herbivores, but can eat omnivores, and occasionally other carnivores.

Definition: The larva of a butterfly or moth, which has a segmented body resembling a worm with three pairs of true legs and several pairs of leg-like appendages

Example sentences:

• Flying to several sites to deposit eggs is a strategy used by all moths and butterflies whose caterpillars must hide from predators.

Definition: warn strongly; put on guard

Example sentences:

• The association cautioned that escaping moths could contaminate nearby farms and endanger their organic certification.

It took astronomers a century after the discovery of the first celestial spiral to prove that the Milky Way itself looks like a giant spiral.

The Hubble Space Telescope, which in 2015 completes 25 years in orbit, has gathered dramatic new views of two well-known celestial objects.

Comets, celestial bodies of dust, ice and complex molecules, are remnants of the birth of our 4.6 billion-year-old solar system.

Definition: Made of clay and permanently hardened by heat

Example sentences:

• Remove from heat, pour into a ceramic bowl, add fifteen drops each of the lavender and sandalwood essential oil and beat until cool and creamy.

Definition: completely unordered and unpredictable and confusing

Example sentences:

• She focused on the positive aspects of chaos of being a mother: Things are chaotic because she has two beautiful children and a thriving career.
• Among the employees here are a handful of disabled workers — often forgotten in a country that is too chaotic to attend to them.

Definition: be typical or characteristic of

Example senences:

• The disease is characterized by weakening of the immune system.
• It was a social relationship characterized by an unequal distribution of power and resources.

Definition: a personal attractiveness or interestingness that enables you to influence others

Example sentences:

• He was known for this charismatic personality

Definition: for the most part

Example sentences:

• Heroin abuse is soaring, thanks chiefly to its cheap price and widespread availability.

Definition: A thread-like structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

Example sentences:

• The sex chromosomes are placed to the right of the smallest autosomal chromosomes.

Definition: (Of a record of events) following the order in which they occurred

Example sentences:

• The events are presented in chronological order of occurrence.

Definition: move through a space, circuit or system, returning to the starting point

Example sentences:

• Women who tested positive for circulating tumor DNA were 12 times more at risk of cancer recurrence than those who tested negative.
• No director for the new film has been announced, although rumors have been circulating that James would like to direct the movie himself.

A civilization is a society that has advanced features. For example, the people aren’t barbaric. They have a set of rules, or laws that they follow, as well as political and religious organizations. Civilization can also be a particular society at a certain time and place.

• The archaeologists were impressed with the ancient civilization of the Mayans.

Definition: A category into which something is put.

Example senences:

• Several classifications are used to categorize individual apple trees

Definition: Of, relating to, or near a coast

Example sentences:

• The process of coastal erosion and deposition further down the coast has been going on for centuries.

Definition: The mental action or process of acquiring knowledge and understanding through thought, experience, and the senses.

Example sentences:

• The findings from these experiments have been taken to demonstrate the role of cognition in the experience of emotion.

If it's related to thinking, it's considered cognitive. A child's cognitive development is the growth in his or her ability to think and solve problems. Used in a sentence, “Her cognitive style was much different from my son’s.” or, in other words, her thinking style was much different, or the way that they came to the same answer could have been very different. 

Cognitivity refers to the adjective form of the word and is the state of thinking.

Example sentences:

• As children grow older, their cognitive processes become sharper.
• Estrogen is said to enhance cognitive function.
• I had an aneurysm and my speech was not badly affected, but the singing has really helped to improve my cognitivity and get my confidence back. 

Definition: Denoting animals whose body temperature varies with that of the environment (e.g. fish)

Example sentences:

• Crocodiles are cold-blooded creatures, and they keep their temperature constant by basking in the sun and staying in the water at night.

Definition: Hit when moving

Example senences:

• A youth was killed when a passenger train collided with his car on a level crossing in East Yorkshire last night
• When continental and oceanic plates collide the thinner and more dense oceanic plate is overridden by the thicker and less dense continental plate. The oceanic plate is forced down into the mantle in a process known as "subduction".

Definition: (Of language) used in ordinary or familiar conversation; not formal or literary

Example sentences:

• colloquial and everyday language.

A colonist is someone who settles in a new colony or a new country. Used in an example sentence:

• Trade relationships between the Native Americans and the European colonists spanned from the 1500s to the late 1800s.​

Definition: Come to settle among and establish political control over (the indigenous people of an area)

Example sentences:

• The Bible which has been used as a tool to oppress, subjugate and colonize indigenous people has proved to be even more powerful a weapon than the European's firearms

Colossal can refer to an item's physical size, like a giant redwood tree, but it can also be used to describe the force or scope of something — like the colossal force of a thunderstorm that knocked down the redwood tree, or the colossal scope of your school project on the history of the redwoods that seems like it will never, ever end.  

Example sentences:

• Their business partnership turned out to be a colossal (meaning massive) failure.
• The meeting was a colossal (meaning huge, enormous) waste of time.
• There has been a colossal waste of public money.
• The task they face is colossal.
• The scope of this project is colossal.

Definition: Be consumed or destroyed by fire

Example sentences:

• When fossil fuels are combusted, oxides are emitted into the atmosphere

The verb combust basically has the same meaning of the verb “burn”, and the noun ‘combustion’ basically means “burning”. We use it a lot when we talk about the burning process in car engines and power plants.

• Since fuels require oxygen to combust, reduced oxygen content in the vapor space lowers the risk of unwanted combustion.

• Natural gas is frequently combusted in gas turbines as well as boilers.

• Oxygen, carbon dioxide, and carbon monoxide are all indicators of the efficiency of the combustion process.

Both the asteroid and the comet are large, irregularly shaped objects in space that orbits our Sun. However, while comets are mostly made of ice, asteroids are made up of rock or even metal. 

Commonplace has the same meaning of ‘common’, but it carries a negative meaning of being dull and unchallenging or tired and clichéd.  For example:

• Coffee shops in cities are commonplace.
• Nowadays, distance-learning programs are commonplace, but some people argue that they are not as good as those attending college in person.
• Drug use has become commonplace at rock concerts.
• A commonplace job is a boring, mind-numbing task. 
• In contrast to the United States, where surrogacy is increasingly commonplace and accepted, the practice is generally illegal in Australia.
• In 2017, it is commonplace to see people constantly checking their phones.

Commonplace can be a noun. Things that are common can be found all over the place — they're commonplace! For example:

• We now accept cell phones and laptop computers as commonplaces of everyday life.

We often use the phrase 'It is a commonplace that' to say an idea, expression, remark, etc. that is not new or interesting. In other words, "It is a commonplace that = Everyone knows that" Look at the following example sentences:

• It is a commonplace that we only use a small part of our brain's capacity.
• It is a commonplace that the history of civilization is largely the history of weapons.
• It is a commonplace that American consumers have kept the world economy spinning. 

Definition: an aggressive willingness to compete;

Example sentences:

• Strategic alliance is a common way for two companies to increase competitiveness in a global market.

A composer is a person who writes and performs music for a job. Bach, Beethoven and Mozart are all famous composers.

Definition: A thing that is composed of two or more separate elements; a mixture;A substance formed from two or more elements chemically united in fixed proportions

Example sentences:

• The air smelled like a compound of diesel and petrol fumes. The layers of plants and animals slowly broke down into simple substances called hydrocarbons, compounds of hydrogen and carbon.

Conceivable means the possibility to imagine something. 

Let’s look at some more example sentences where the word “conceivable” is used:

• They discussed the question from every conceivable angle.

This sentence simply means that the question was discussed from every possible angle.

Here is another example sentence:

• It is conceivable that she will refuse to go.

Again, the sentence simply means that it is possible that she will refuse to go.

The word “conceive” is popularly used to describe someone who is pregnant. A conceived woman is a pregnant woman.

Here are example sentences

• She is unable to conceive a child
• Mrs. Brown conceived three children.

Another meaning for "conceive" is to imagine, creating something in mind.  Also, when the word “conceive” is used in a sentence to mean to imagine, creating something in mind, it can be followed by an object or can be used without an object.

Here are some example sentences where the word “conceive” is followed by an object:

• A novelist is able to conceive (meaning imagined) an imaginary world.
• When the writer conceived this role, he had a specific actor in mind to play the part.
• The system was conceived (meaning invented) by a Swedish engineer.

When the word “conceive” is not followed by an object, it is usually followed by the preposition “of” as seen in the following example sentences:

• They conceived of (meaning thought of, regarded) her as a genius.
• I can't conceive of (meaning imagine) a reason for not supporting this policy.

A concerto is a classical music composition that consists of a full orchestra but only highlights the sounds of one instrument. It is often for orchestras to have a soloist, or someone who plays a piece by themselves against the full sounds of the orchestra, but in a concerto, one instrument is highlighted or showcased throughout the entire performance.

To change from a gaseous state into a liquid state, we can use the verb ‘condense’. Here are example sentences:

• The cooler temperatures cause the gas to condense into a liquid.​
• The steam from the shower condenses quickly when it hits the cool window.

Definition: (of information) given in confidence or in secret

Example sentences:

• Employees are instructed to keep confidential documents in secure places.
• He locked the confidential documents in his filing cabinet.
• Someone is leaking confidential information on the investigation.
• I would like to invite you to participate in this research project. This would involve you completing a short online questionnaire. It is expected that the questionnaire will take about 25 minutes to complete. If you consent to participate, your responses will be kept confidential.

Definition: Compliance with standards, rules, or laws

Example senences:

• The staff expressed the hope that the administration and governing board would act in conformity with these standards. (be in conformity with)

Congregate is a verb that means to come together. The usage “congregate in groups/herds” is often used. Here are example sentences

• Penguins congregate in groups to stay warm. These group congregation facilities reproduction in extreme temperatures.
• The prey animals evolve to congregate in herds, for the protection it provides from predators, as well as the help it provides in finding food and mates.
• Buffalo congregate in larger herds to defend against attacks from predators such as lions.
• White-tailed jackrabbits are the most solitary of all the hares. However, they congregate into groups of one hundreds or more when food is abundant.

Definition: The action or an instance of two or more events or things occurring at the same point in time or space:

Example sentences:

• The conjunction of events marks a widening of the challenge posed by San Francisco's mayor, who last month authorised wedding ceremonies for same-sex couples.

Definition: characterized by extreme care and great effort; guided by conscience or sense of right and wrong

Example sentences:

• It’s well-known that personality influences professional prowess, as high earners tend to be extraverted, ambitious, conscientious and self-confident.
• The purpose of college is to create conscientious, thinking individuals who know how to function in society.

One word that has the similar meaning of result is "consequence". However, the noun consequence is most frequently used to talk about negative results of an action. It is commonly used with such words as "adverse",  "disastrous", "fatal", "harmful", "negative", "serious", "tragic' and "unfortunate". 

For example,

• When people do something wrong, like rob a bank, the consequence will probably be prison time.
• When something occurs in nature, like a tornado touching down, destruction might be a disastrous consequence.

The following patterns and expressions are commonly used with the noun consequence.

• B is a consequence of A
• When/If ___, the consequence is B
• A has a consequence.
• The consequence of A is B.

Here are example sentences:

• Depletion of natural resources is a consequence of rapid industrial development.
• When humans exploit natural resources, the consequence can be the loss of natural habitats.
• The exploitation of natural resources has serious consequences.
• The consequences of oil spills are disastrous to many plants and animal marine life.

Definition: A person who advocates or acts for the protection and preservation of the environment and wildlife:

Example sentences:

• The plan is signed by eminent ecologists and conservationists from around the world.

Use the adjective considerable to describe something that is large in amount or in number. Things you probably spend a considerable amount of time on: homework and laundry.  Example sentences using the word considerable:

• We've saved a considerable amount of money and are ready to buy our first house.
• This will not be an easy task, and it will require a considerable amount of time and effort on our part.
• Vets' fees can be considerable, even for routine checkups. The good news is that we can lower the costs of some common veterinary services considerably with pet insurance.
• Canada Air has purchased five more double-deck jets and has refurbished its existing airplanes to include seats with considerable legroom and computers with video and gaming features.
• In 2017, Line Friends, one of Asia's most popular tech companies, collaborated with Korean idol group BTS on a line of characters called BT21, playing a considerable part in the company's expansion. 

Definition: in a systematic or consistent manner

Example sentences:

• The show seems as if it will build to some towering finale, but instead it keeps teetering along at the same consistently high mark.

Definition: attracting attention

Example sentences:

• The movie will probably be more popular with audiences than with critics, perhaps because it’s so deliberately and conspicuously old-fashioned.
• Her name was conspicuously absent form the list of winners.

Definition: Be (a part) of a whole

Example sentences:

• Europe was increasingly concentrating power into the hands of elite groups, who constituted a very small proportion of the total population.

Consumer- A consumer is someone who buys or consumes, or uses up, something. An economy could not continuously function without consumers. If you buy goods and services for your personal use you are a consumer. We're all consumers when we go through the checkout line at the grocery store. 

Example sentences using consumer

• A study shows that Generation X consumers made more online purchases than any other age group, averaging nearly 20 transactions per year.
• I think there is a growing trend among consumers for mushrooms. In fact, change in consumer preferences toward vegan food and rise in demand for meat substitutes are expected to propel the mushroom market growth in the future.
• Our company saw an opportunity and launched a new product in the summer of 2021 that speaks directly to health concerns consumers have during the pandemic. 

Consumer goods/products mean products that people buy for personal use or for use at home. Consumer spending is what households buy to fulfill everyday needs. This private consumption includes goods and services.

Let's look at this example:

• In order to reduce the need for warehouse space, more and more grocery retailers now require suppliers to deliver consumer goods "just in time" to replenish stocks on the sales floor.
• Consumer spending declined 0.1 percent year-on-year in November.
• The drop in consumer spending reflects concern about the economy.
• U.S. consumer spending rose more than expected in April as households boosted purchases of goods and services.

Definition: (NOUN) contaminate

Example sentences:

• Groundwater pollution generally results from contaminants leaching through soils to underlying aquifers.

Contemporary is an adjective to describe anything happening now, or in the same time. Contemporary art is new art, and has been developed recently. You could think of contemporary and modern belonging in the same word group, especially when related to art.

• She didn’t like the looks of the old architecture, and was looking for something more contemporary.

A continent is a very large area of land, such as Africa or Asia, that consists of several countries.

If two or more facts, pieces of advice, etc. are contradictory, they are very different from each other.

Example sentences using the word contradictory:

• I keep getting contradictory advice - some people tell me to keep it warm and some tell me to put ice on it.
• The evidence is completely contradictory.
• The argument is internally contradictory (meaning contradicts itself).
• The two studies came to contradictory conclusions.

The word contributing can be used to describe things that help to bring about results, whether positive or negative.

Ok! Let’s take a look at the sentences below of the word contributing:

• The coach's positive attitude was a contributing factor to the team's success. 
• She has been a contributing writer for the magazine for 10 years.
• If you're a contributing voice in the audience at a noisy rock concert, it means you're screaming your head off. 
• If you're a contributing member of your friend's fundraising efforts, it means you're giving her money. 

When you write cause and effect sentences in TOEFL writing section, you can use the phrase "a contributing factor to" instead of "contribute to". Here is an example:

• Deforestation is a major contributor to climate change = Deforestation significantly contributes to climate change.

A contrivance can also mean a gadget or device that can be used for some particular purpose. An example sentence would be

• This modern contrivance [=devices] can cook food faster.

The word sometimes also implies a falseness or obviousness. In this case, a contrivance is an unfair or dishonest scheme or trick to gain an advantage for yourself.

Definition: marked by or capable of arousing controversy

Example sentences:

• Vitamin D is a controversial topic among doctors, mainly because studies about its health effects have been so conflicting.
• The Coca-Cola Company yesterday revealed some details about its controversial role as a supporter of obesity research.

Definition: Coming closer together; converging

Example senences:

• The volcanically active trail-ends are preferentially located near divergent plate boundaries and are rare near convergent boundaries.

Copious is a word to describe a large amount of something.

copious amounts of something = large/vast/immense/enormous amounts of something

Example sentences:

• The storm produced a copious amount of rain.
• I have a copious amount of work I have to do before I can leave the office.
• She sat in the front row and took copious notes during the lecture.
• Los Angeles has a copious amount of automobiles.

Definition: A ridge of rock in the sea formed by the growth and deposit of coral:

Example sentences:

• Offshore drilling would damage coral reefs and mangrove swamps and threaten endangered sea life.

Definition: The process of corroding or being corroded

Example senences:

• This is because the iron electrode is more susceptible to corrosion and to self-discharge on standing.

Definition: The outer layer of the cerebrum (the cerebral cortex), composed of folded grey matter and playing an important role in consciousness.

Example sentences:

• Careful prospective and controlled studies of autonomic function will clarify the roles of the cortex and the brainstem in the generation and expression of seizures.

Definition: not genuine; imitating something superior; a copy that is represented as the original

Example sentences:

• Many veggie burgers taste processed and counterfeit, it is difficult for the new burger chain to dominate the market overnight.
• Merchants that sell big-ticket items and smaller items, such as gift cards, that can be easily resold are most vulnerable to counterfeit fraud.

The courtship of male and female animals is their behavior before they have sex. An example in a sentence:

• The courtship of male and female animals is their behavior before they have sex.
• The ultimate purpose of courtship is to attract a receptive mate. Different courtship behaviors also serve to reduce territorial aggression.

Definition: move slowly; to begin to happen

Example sentences:

• Some mistakes are beginning to creep into his work.
• They were caught by surprise when the three men crept up from behind and yelled, “Nobody move.”

Definition: A deep open crack, especially one in a glacier.

Example sentences:

• On good days they could travel no more than 15 miles, and they had to be ever vigilant of the deep crevasses opening up beneath their feet when the snow melted.

Definition: Cause severe and disabling damage to (a machine); Cause a severe and almost insuperable problem for

Example sentences:

• We have developing countries being crippled by debt, so we need a more value-led globalization.

Definition: A large predatory semiaquatic reptile with long jaws, long tail, short legs, and a horny textured skin, using submersion and stealth to approach prey unseen. The crocodile has been extensively hunted for its valuable skin

Example sentences:

• Hunted extensively for their skins, large crocodiles are becoming increasingly rare.

Crops are plants such as wheat and potatoes that are grown in large quantities for food. Farmers grow/harvest/cultivate crops

Example sentences:

• Rice farmers here still plant and harvest their crops by hand.
• The main crop is wheat and this is grown even on the very steep slopes.

Crucial means very important. Example sentences:

• This is a crucial moment for the company.
• Early detection is crucial in the fight against breast cancer.
• Knowing how many products we have in stock is crucial to our shipping procedures.
• Price will be a crucial factor in the success of this new product.
• If no one is purchasing the product you are selling, you can keep waiting, or start asking questions. Is your packaging effectively showcasing the benefit of your product? Is your price point off? Ask retailers and your customers what was wrong. Their feedback is absolutely crucial. 

Definition: An arthropod of the large, mainly aquatic group Crustacea, such as a crab, lobster, shrimp, or barnacle.

Example sentences:

• Marine scientists have found evidence of similar patterns among shoreline species like crabs, crustaceans and seaweed.

Definition: Having the structure and form of a crystal; composed of crystals

Example sentences:

• This crystalline structure is an orderly arrangement of ions known as a crystal lattice.

If you cultivate land or crops, you prepare land and grow crops on it. Cultivation is the act of cultivating.The adjective cultivable describe land that can be cultivated.

Here are example sentences

• It is believed that due to climate change, people moved from animal hunting to gathering and agriculture. About 10,000 years ago, some human groups began to raise animals and cultivate domesticated plants.
• Prehistoric peoples settled the area and began to cultivate the land.
• Some of the fields are cultivated while others lie fallow.
• The burning of woodland created an open clearing for the cultivation of hazel trees and grazing animals.  
• In the past cultivation of crops was a labor-intensive process.
• Arid land is unsuitable for many crops and must be irrigated in order for cultivation to take place.
• Cultivable land can be used to grow crops.
• Most of the island isn't cultivable - the soil is too rocky.

If you cultivate land or crops, you prepare land and grow crops on it. Cultivation is the act of cultivating.The adjective cultivable describe land that can be cultivated.

Here are example sentences

• It is believed that due to climate change, people moved from animal hunting to gathering and agriculture. About 10,000 years ago, some human groups began to raise animals and cultivate domesticated plants.
• Prehistoric peoples settled the area and began to cultivate the land.
• Some of the fields are cultivated while others lie fallow.
• The burning of woodland created an open clearing for the cultivation of hazel trees and grazing animals.  
• In the past cultivation of crops was a labor-intensive process.
• Arid land is unsuitable for many crops and must be irrigated in order for cultivation to take place.
• Cultivable land can be used to grow crops.
• Most of the island isn't cultivable - the soil is too rocky.

Definition: monetary unit; cash

Example sentences:

• Most purchases in foreign countries must be made in the local currency.

Notice the root word in “customary” is “custom”, so the two words are very similar. Something customary is done according to practice. For example,

• When a bride walks down the aisle, it's customary for everyone at the wedding to rise out of respect.

Every culture has its own customary traditions. In American culture, it's customary for a child who loses a tooth to put it under her pillow and wait for the Tooth Fairy to arrive. In Greece, on the other hand, it's customary to throw a child's lost tooth onto the roof for good luck.

Customary can also reference habitual things a person does, like taking your shoes off when you come home or writing in your diary before bed. Used in a sentence, “In America, it is customary for the bride to wear something blue on her wedding day.”