4. My brother used to have his hair cut short when he joined the army.

5. Dennis used to smoke 3 years ago.

6. My parents used to live in the USA when they were young.

7. Jim used to be my best friend, but we aren't friends any more.

8. When he was younger, my uncle used to be a national swimming champion.

Ex9:

1. to dream

2. to speaking

3. to living

4. to stop

5. to work

6. to drinking

7. to being

8. to have

9. to be

10. to driving

1, to dream

2, to speaking

3, to living

4, to stop

5, to work

6, to drinking

7, to being

8, to have

9, to be

10, to driving

(get/ to be + used + to + Ving: quen với cái gì, có thói quen làm gì

Used to V: đã từng làm gì)