Câu hỏi: After the police had tried unsuccessfully to determine to who the car belonged, they towed it to the station.

A. the police

B. unsuccessfully

C. who

D. it to

Câu 1: Had it not been for you help me, I wouldn't have succeeded.

A. not

B. you help me

C. wouldn’t

D. succeeded

Câu 2: It is vitally important that she takes this medication night and morning.

A. vitally

B. that

C. takes

D. medication

Câu 3: By the time Robert will finish writing the first draft of his paper, most of the other students will have completed their final draft.

A. will finish

B. writing

C. most

D. their

Câu 4: Developing new technologies are time-consuming and expensive.

A. developing 

B. technologies

C. are

D. time-consuming

Câu 5: What we know about certain diseases are still not sufficient to prevent them from spreading easily among the population.

A. What we know

B. are

C. from spreading

D. among

Câu 6: Some species of bats are dormant each days and active every night.

A. species of

B. each days

C. every night 

D. are dormant