Exercise 21, Page 97
1.     Will understand
2.     Wouldn’t have been
3.     Will give
4.     Would have told
5.     Would have been
6.     Had
7.     Would stop
8.     Needed
9.     Would have found
10.   Enjoyed
11.   Will paint
12.   Were
13.   Will write
14.   Permited
15.   Would spend
16.   Will accept
17.   Buy
18.   Had decided
19.   Had written
20.   Will leak
21.   Could study
22.   Will hear
23.   See
24.   Get
25.   Turn
26.   Will be
27.   Would have called
28.   Would have talked
29.   Explained
30.   Spoke

Exercise 22, Page 99
1.     Eating
2.     Eat
3.     Swim
4.     Like
5.     Speaking
6.     Studying
7.     Dance
8.     Sleeping
9.     Eating
10.   Eating

Exercise 23, Page 101
1.     Stay
2.     Have stayed
3.     Work
4.     Studied
5.     Not study
6.     Have
7.     Stood
8.     Not cook
9.     Had not arrived
10.   Have slept
Exercise 24, Page 103
1.     Should have had
2.     Must have be sick
3.     May have damaged
4.     Shouldn’t have parked
5.     Must have studied
6.     Must have studied
7.     Could have been
8.     Must have deposited
9.     Might have forgotten
10.   Must not have studied

Exercise 25, Page 105-106
1.     I would
2.     Would go
3.     May have had
4.     Must have done
5.     Must have forgotten
6.     May have slept
7.     Might have had
8.     Could have lost
9.     Should have driven
10.   May have run