Поставьте «to» перед инфинитивом там, где это необходимо:
1. You must make him … practice an hour a day.
2. He is not sure that it can … be done, but he is willing … try.
3. She was seen … leave the house.
4. Have you heard him… play the piano?
5. You had better … go there at once.
6. Let me … help you with your work.
7. I would rather not … tell them about it.
2)-;to
3)-
4)-
5)to
6)-
7) to