20.
1) Do, don't.
2) Doesn't, does.
3) Does, doesn't.
4) Don't, do.
5) Does, does.
23. 1. runs.
2. Не надо.
3. cooks.
4. Не надо.
5. swims
6. comes
7. goes
8. Не надо
9. Не надо
10. likes
11. eats
12. Не надо
13. Не надо
14. sees
15. Не надо
16. skies
17. Не надо
18. boys
19. boys
20. Не надо
21. Не надо
22. likes bananas
23. drinks
24. Не надо