Change into passive.
1 We must wait for him
1
2 I should have called her
2
3 My father has to do it
3
4 They can’t speak English
4
5 He might find out the truth
5
6 I used to do that
6
7 We shall win the fight
7
8 She may expect a reward
8
9 They ought to write a complaint
9
10 He could have stolen the document
10