Trang 2:
1. is watching
2. aren't sitting
3. are learning
4. is playing
5. is sleeping
6. are singing
7. is writing
8. is working
9. isn't watching
10. is playing
11. are you working
12. is she doing
13. aren't reading
14. is rsing
15. is washing
16. am looking
17. is knocking
18. are shopping
19. are meeting
20 is sitting

trang 3:
1. was
2. started
3. stopped
4. saw
5. did you go - was
6. drank
7. wasn't - didn't enjoy
8. used
9. went - didn't tell
10. did Mr, Thomas die
11. was the weather be
12. worked
13. wrote
14. broke
15. discovered
16. had
17. did Nam buy
18. got
19. didn't see
20. met

1. get
2. dosen't
3. plays
4. do you go
5. are you come
6. takes
7. smokes
8.dose Ton watch
9. gose
10. is
11. is
12. studeien
13. Dose your brother takke
14. comes
15. speaks
16. watch
17. likes
18. washes
19. studies
20. wants
21 often don't work
22. has