6. They have built a perfect dam across the river.

A. Across the river a perfect dam was built.

B. A perfect dam has been built by them across the river

C. A perfect dam should have been built by them.

D. Across the river was a perfect dam

7. Do you imitate others?

A. Are others being imitated by you?

B. Are others imitated by you?

C. Have others being imitated by you?

D. Were others being imitated by you?

8. You need to clean your shoes properly.

A. Your shoes are needed to clean properly.

B. You are needed to clean your shoes properly.

C. Your shoes need to be cleaned properly.

D. Your shoes are needed by you to clean properly.

9. He is said to be very rich

A. He said he is very rich

B. People say he is very rich

C. He said it is very rich.

D. People say it is very rich.

10. The invigilator was reading out the instructions.

A. The instructions were read by the invigilator.

B. The instructions were being read out by the invigilator.

C. The instructions had been read out by the invigilator.

D. The instructions had been read by the invigilator.