Zizi's sentences

1) Active: Somebody stole my mobile yesterday.
Passive: My mobile was stolen yesterday.

2) Active: Nadra bought a laptop last night.
Passive: A laptop was bought by Nadra last night.

3) Active: People always invite me to parties.
Passive: I am always invited to parties.

4) Active: Alanoud bought a flash drive this morning.
Passive: A flash drive was bought by Alanoud this morning.

5) Active: When did they build this house?
Passive: When was this house built?