1.

=> A house is being built, isn't it?

=> Are they building a house?

2.

=> This letter cannot be opened, can it?

3.

=> A new school is going to be opened here, isn't it?

=> Are they going to open a new school here?

4.

=> The clothes are being washed by your brother, aren't they?

5.

=> This church was built in 1973, wasn't it?

=> Did they build this church' in 1973?

6.

=> English is taught in your school, isn't it?

=> Do they teach English in your school?

7.

=> His story is not believed by anybody.

8.

=> Did they ask me many difficult questions?

9.

=> My piano is being repaired, isn't it?

=> Are they repairing my piano?

10.

=> A lot of homework is being done by students, isn't it?

=> Are students doing a lot of homework?

11.

=> Our children was looked after, didn't they?

=> Did she look after our children?

12.

=> This room hasn't been used for ages.

13.

=> The dog was hit in the garden by the boy yesterday, wasn't it?

=> Did the boy hit the dog in the garden yesterday?