хз, наверное так:

1. wasn't he

2. aren't they

3. can she

4. haven't been you

5. weren't they

6. is he

7. could you

8. are you

9. can't she

10. is he

11. were they

12. has she

13. couldn't you

14. was she

15. can you

16. were they

17. haven't we

18. aren't we

19. is he

20. could she