1. is singing
2. go
3. likes/like
4. are staying
5. reads
6. is running
7. listens
8. is/is/is watching
9. are they going
10. are
11. doesn't go
12. go/go
13. am writing
14. have/ go
15. have
16. have
17 am eating/ is playing
18. is looking/ is eating
19. are ( 4 người Phong, An, Hà, lan là số nhiều ⇒ to be cx chia số nhiều
20. what are you doing now( now là dấu hiệu của thì HTTD)