III:

1: caused

2: are going to see

3: speak

4: wrote

5: did.....learn.....teached

6: go.....went

7: introduced

8: was.....didn't have

9: will.....do.....will visit

10: to come

11: playing

12: to go

13: received

14: to go

15: did.....spend

16: came

17: are playing

18: won't go

19: teached

20: is taking

1: caused

2: are going to see ( thì HTTD )

3: speak ( can/could/should/have/... + V - infi )

4: wrote ( thì QKĐ ) 

5: did.....learn.....teached ( thì QKĐ )

6: go.....went ( thì HTĐ và QKĐ )

7: introduced ( QKĐ )

8: was.....didn't have ( QHĐ )

9: will.....do.....will visit ( TLĐ )

10: to come ( Would ... to + V-infi )

11: playing ( enjoy,like,love,... + V-ing )

12: to go ( enough + to + V-infi )

13: received ( QKĐ )

14: to go ( Would ... to V-infi )

15: did.....spend ( QKĐ )

16: came ( QKĐ )

17: are playing ( HTTD )

18: won't go ( TLĐ )

19: teached ( QKĐ )

20: is taking ( HTTD )