3.

1.Did you use to go to school on foot?

2.Mr.Van didn't use to ride his motorbike dangerously.

3.Did the streets use to be cleaner and more peaceful?

4.I used to go out on Sundays.

5.They didn't use to go on holiday together.

4.

1.It is over 100 km from my hometown to Ho Chi Minh City.

2.It is about 25 km to my grandparents’ house.

3.I used to ride a small bike in the yard outside my flat.

4.There used to be a bus station in the city centre, but it was/ has been moved to the suburbs.

5.Children must learn about road safety before they are allowed to ride a bike on the road.

5.

1.b

2.a

3.e

4.d

5.f

6.c