1) I didn't often go to the supermarket every Sunday last year

⇒ I didn't use to go to the supermarket every Sunday last year

2) Her hair now is much longer than that in the past

⇒ In the past, her hair used to be shorter

3) I didn't collect dolls when I was in the secondary school

⇒ I used to collect dolls when I was not in the secondary school

4) Did she often go to the beach when she lived in Hai Phong?

⇒ Did she use to go to the beach when she lived in Hai Phong?

5) mI usually stayed up late to do my homework last year, but now I don't

⇒ I used to stay up late to do my homework last year

6) There were some flowers in the field, but now there aren't any

⇒ There used to be some flowers in the field

7) Peter doesn't live with his parents any more

⇒ Peter used to live with his parents

@Haki113