Câu hỏi: The big problem was that we really did not understand what was happened

A. problem

B. that

C. did not

D. was happened

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 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: 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 4: 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 5: Parks which are found in downtown areas where office workers and store employees can enjoy their lunch hours sitting on the green grass in clean, fresh air.

A. which

B. employees

C. lunch hours sitting

D. fresh air

Câu 6: Each of the nurses report to the operating room when his or her name is called.

A. of the

B. report

C. his or her name

D. is called