1. C
2. D
3. B
4. D
5. C
6. B
7. B
8. C
9. C
10. A
11. D
12. C
13. C
14. C
15.
16. B
17. That → which
18.
19. be killed → killing
20. Mai, whom we love so much, is good at Maths.
21. Last week, I went to the house where I used to live in.
22. A man who said Tom was out answered the phone.