16, meeting
17, to give
18, not going
19, speaking
20, to understand
21, drinking
22, to write
23, smoking
24, to answer
25, going
26, to camp
27, to buy
28, spending
29, saying
30, to do

EXERCISE 4:
79, I am looking forward to receiving the letter now.
80, We don't mind waiting more minutes.
81, Children are busy to collect the shells in the beach.
82, He asked us to help him to do the washing up the day before.

6. seeing
7. traveling
8. to get
9. arguing / to work
10. to have
11. to seeing
12. not touching
13. to disappoint
14. to sign
15. going
16, meeting
17. to give
18. not going
19. speaking
20. to understand
21. drinking
22. to write
23. smoking
24. to answer
25. going
26. to camp
27. to buy
28. spending
29. saying
30. to do