Câu hỏi: She did not know where most of the people in the conference was from.

A. did not

B. where

C. the

D. was

Câu 1: The harder he tried, the worst he danced before the large audience.

A. before

B. the

C. worst

D. tried

Câu 2: My father asked me where had I gone the night before.

A. asked

B. the 

C. before

D. had I

Câu 3: There are many reasons why a particular species may become endangering.

A. endangering

B. may

C. a

D. reasons why

Câu 4: It is important that you turned off the heater every morning before you leave for class.

A. turned off

B. before

C. important

D. leave for

Câu 5: If I had studied carefully, I wouldn't made so many mistakes.

A. I had

B. carefully

C. made

D. so many

Câu 6: I can’t go out tonight because I have too many work to do.

A. can’t

B. because

C. too many

D. to do