Câu hỏi: 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 1: If I had studied carefully, I wouldn't made so many mistakes.

A. I had

B. carefully

C. made

D. so many

Câu 2: There are many reasons why a particular species may become endangering.

A. endangering

B. may

C. a

D. reasons why

Câu 3: Both Mr. and Mrs. Smith are explaining the children the rules of the game.

A. Both Mr. and Mrs. Smith

B. are

C. explaining

D. the children the rules of the game

Câu 4: Publishing in the UK, the book has won a number of awards in recent regional book fairs.

A. publishing

B. has won

C. in

D. book fairs

Câu 5: Most of the houses on the street was built in the previous century.

A. of

B. on

C. previous

D. was

Câu 6: The teacher together with his students have finished their project on time.

A. The

B. together 

C. have

D. their