Câu hỏi: Before went abroad, he had finished his English course at the English-speaking Center.

A. went

B. abroad

C. had finished

D. English-speaking

Câu 1: The mother asked her son if he would have the floor clean the day before.

A. asked

B. if

C. would have

D. clean

Câu 2: Unless there had been a heavy storm, the climbers will not have died.

A. Unless

B. had been

C. heavy

D. will

Câu 3: Ecologists are trying to preserve our environment for future generations by protecting the ozone layer, purifying the air, and have planted the trees that have been cut down.

A. to preserve

B. for

C. the ozone layer

D. have planted

Câu 4: Please tell us the reason when he left without saying goodbye.

A. tell

B. when

C. left

D. saying

Câu 5: Conservation is the safeguarding and preservation of nature resources.

A. is

B. safeguarding

C. preservation

D. nature

Câu 6: In spite of my father is old , he gets up early and does morning exercise.

A. In spite of

B. is

C. gets up

D. does morning exercise