1. The door of the house couldn't be opened
2. I asked him how he went to school the day before.
3. He is fond of collecting old coins.
4. She asked Jack if he had got a new car.
5. He told her to give his regards to her parents.
6. I wish your friends were at this party.
7. She told me not to talk to that man.
8. Their homework hasn't been finished (by them) yet.
9. This mathematical problem couldn't be solved/This mathematical problem was too difficult to be solved
10. He told that He didn't know what to do.