1. Gravity makes water run downhill
→ Water
2. People have believed that he kidnapped her.
→ He
3. You'd better explain the difficulty to him
→ The difficulty
4. Who gave you the gift?
→ By whom were
5. Whom did Pike tell about that yesterday?
→ Who was
6. Whom do you take out to dinner?
→ Who is
7. When did you send the school report to them?
→ When was the school report
8. People say that Arthur is very rich.
→ It iss said that
9. They think that he is very intelligent.
→ He is
10. I believe that you will work hard.
→ It is
11. They didn't but anything from the supermarket
→ Nothing was
12. Jane will complete the reports tomorrow.
→ The reports
13. When did they design this building?
→ When was
14. They know that he is very honest.
→ He
15. They think that many people were killed in the accident.
→ Many
16. He made her cry
→ She
17. They let me go
→ I
18. I had him repair motorbike
→