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: The guide told the tourists that it was a good restaurant specializing in seafood just round the corner from the museum.

A. The

B. it was a

C. specializing

D. just round

Câu 2: 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 3: The Red Cross organizes and leads relief assistance missions after natural disasters such as floods, tsunamis, earthquakes, and homelessness.

A. The Red Cross

B. organizes and leads

C. assistance missions

D. and homelessness

Câu 4: Ours brains are incredibly agile machines, and it's hard to think of anything they do more efficient than recognize face.

A. are

B. anything

C. efficient

D. recognize

Câu 5: The office manager insists that his staff use all of their vacation time, but he hardly never takes a vacation himself.

A. insists

B. use

C. their

D. hardly never

Câu 6: 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