Câu hỏi: We were quite impressed by the ______ students who came up with the answer to our question almost instantly.

A. absent-minded

B. big-headed

C. quick-witted

D. bad-tempered

Câu 1: A _____ is a tube through which a person swimming just under the surface of the sea can breathe.

A. maneuver

B. photograph

C. volume

D. snorkel

Câu 2: The world’s biodiversity is declining at an unprecedented rate, which makes wildlife ________.

A. prosperous

B. vulnerable 

C. prefect

D. remained

Câu 3: My father is in_______ of 30 engineers and 80 workers.

A. pressure

B. leadership

C. impression

D. charge

Câu 4: Make sure you ______ up the data on your computer, because you might get a virus.

A. back

B. store

C. save

D. copy

Câu 5: His work ______ new ground in the treatment of cancer. It is now giving many cancer victims hope of complete recovery.

A. broke

B. found

C. dug

D. uncovered

Câu 6: The trouble with James is that he never __________on time for a meeting.

A. turns up

B. takes off

C. takes up

D. turns down