1. They don’t take any part in local life. It’s silly of them.

It’s silly of them to not take any part in local life.

2. It’s a cross-country vehicle with five doors. 

It’s a five-door cross-country vehicle

3. You do not have to pay for secondary education in Britain.

Secondary education doesn't have to be paid for in Britain.

4. This is the quickest way to get into the center of the city.

There is no quicker way to get into the center of the city than this way.

5. Nam only has a little free time; Lan has a lot.

Nam has much less free time than Lan