Câu hỏi: As there was a power cut in the hospital, the surgeon had to _____ the operation.

A. call for

B. call on

C. call off

D. call out

Câu 1: The fog made it difficult for the driver to see when the traffic lights _____.

A. adjusted

B. moved

C. changed

D. removed

Câu 2: It isn’t quite ______ that he will be present at the meeting.

A. right

B. exact

C. certain

D. formal

Câu 3: The country has a system of ______, most of which date from the nineteenth century.

A. channels

B. rivers

C. streams

D. canals

Câu 4: Several prisoners _______ from their guards and escaped.

A. broke away

B. broke out

C. broke through

D. broke down

Câu 5: Do you mind if I ______ with my work while you are getting tea ready?

A. turn to

B. carry out

C. come on

D. carry on

Câu 6: As we wait no longer for the delivery of your order, we have to ______ it.

A. postpone

B. refuse

C. return

D. cancel