=>
V/
1. didn't use to
2. used to
3. didn't use to
4. didn't use to
5. used to
VI/
1. Another problem is the increase in the number of cars on the road.
2. There are many transport rules but many people don't seem really interested in following them.
3. The traffic is worst during rush hours when everyone is trying to get to work or get home quickly.

V.
1. did not use to
2. used to
3. did not use to
4. did not use to
5. used to
VI.

1. Another problem is the increase in the number of cars on the road.

Dịch

1. Một vấn đề khác là số lượng ô tô trên đường ngày càng tăng.