curious

definition: 
eager to investigate and learn or learn more (sometimes about others' concerns)
sentence: 
I was curious to know whether there was any physical addiction to doping that might lead an athlete into recidivism.
difficulty: 
very easy
toefl frequency: 
3
toefl classification: 
adverb: 
curiously
adjective: 
curious
adverb sentence: 
While I was snapping pictures of the center's exterior, an employee cracked opened the door and looked at me curiously.
adjective sentence: