Câu hỏi: 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 1: 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 2: The longer the children waited in the long queue, the more impatiently they became

A. the longer

B. waited

C. the long queue

D. impatiently

Câu 3: It is vitally important that she takes this medication night and morning.

A. vitally

B. that

C. takes

D. medication

Câu 4: United States is aimed at develop friendly relations among nations based on respect for the principle of equal rights and self-determination of people.

A. develop

B. based

C. principle

D. people

Câu 5: If you work hard, you would be successful in anything you do.

A. you work

B. would be

C. in

D. anything

Câu 6: It is important that cancer is diagnosed and treated as early as possible in order to assure a successful cure.

A. is diagnosed

B. treated

C. as early as possible

D. to assure