Câu hỏi: A beaver uses its strong front_teeth to cut down trees and peel_off its bark.

A. its

B. front teeth

C. eel off

D. its

Câu 1: These snakes will not cause you any serious harm. They are harmful.

A. snakes

B. cause

C. harm

D. harmful

Câu 2: The eastern bluebird is considered the most attractive bird native of North America by many bird-watchers.

A. bluebird

B. considered

C. native of

D. by

Câu 3: The clerks who are happy to wait for their customer will get promoted soon.

A. clerks

B. wait for

C. customer

D. get promoted

Câu 4: There was a gradual raise in the number of literate males and females in the lowlands.

A. a gradual

B. raise

C. literate

D. the lowlands

Câu 5: Species like snakes, lizards, coyotes, squirrels, and jack rabbits seems to exist quite happily in the desert.

A. like

B. seems to

C. quite happily

D. the

Câu 6: Women nowadays have more free to participate in social activities.

A. nowadays

B. more

C. free

D. social