Ex. 2
a
2 I didn't use to behave
3 We used to wear
4 Did Alex use to have
5 didn't use to study
6 used to be
7 We didn't use to play
8 Did your teachers use to give
b
2 He used to go
3 We didn't use to understand
4 Did you use to go
5 School used to
6 Did your friends use to help
