Submitted by admin on Fri, 04/18/2014 - 15:49
definition:
An animal lacking a backbone, such as an arthropod, mollusk, annelid, coelenterate, etc. The invertebrates constitute an artificial division of the animal kingdom, comprising 95 percent of animal species and about 30 different phyla
sentence:
During the breeding season they eat mostly insects and other invertebrates.
difficulty:
hard
toefl frequency:
1
toefl classification: