Câu hỏi: We must take steps to preserve natural resources; otherwise the planet will be in danger. 

A. Unless we take steps to preserve natural resources, the planet will be in danger. 

B. Unless we take steps to preserve natural resources,the planet will not be in danger.

C. If we take steps to preserve natural resources, the planet would be in danger.

D. If we take steps to preserve natural resources,the planet will be in danger. 

Câu 1: People have discovered a new source of energy. 

A. A new source of energy have been discovered by people.

B. A new source of energy has discovered.

C. A new source of energy has been discovered.

D. A new source of energy have been discovered. 

Câu 2: Don't forget to come here in time,            ?

A. can you

B. will you

C. do you

D. are you

Câu 3: “I would study English if I were you,” Mai’s friend said. 

A. Mai’s friend advised her to study English.

B. Mai’s friend advised her to have studied English.

C. Mai’s friend said that she was like Mai.

D. Mai told her friend to study English.

Câu 4: We decided to go out for dinner _________it was raining heavily. 

A. because

B. despite 

C. even if

D. although

Câu 5: The car was so expensive that I didn’t buy it

A. The car was not so cheap that I couldn’t buy it. 

B. The car was such expensive that I didn’t buy it. 

C. The car was cheap enough for me to buy

D. The car was too expensive for me to buy

Câu 6: The police had to let her _________ because of insufficient evidence. 

A. go

B. to go 

C. going 

D. gone