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

A. snakes

B. cause

C. harm

D. harmful

Câu 1: 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 2: Practicing his speaking English everyday, his hope was to get a good job in a foreign company.

A. his

B. everyday

C. his hope

D. to get

Câu 3: Doctors believe there is better in this modern world of ours to try to prevent illnesses than to rely on medicines to cure them.

A. doctors

B. there is

C. of ours

D. to

Câu 4: The developing of the submarine was hindered by the lack of a power source that could propel an underwater vessel.

A. developing

B. the

C. a power

D. could propel

Câu 5: The freshman failed to follow the advice of her senior that he studied hard and not go out too much.

A. freshman

B. her

C. studied

D. not go out

Câu 6: 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