1. Some people prefer coffee over milk.
2. Most teenagers rely too much on their parents.
3. Any of these could be his.
4. Everybody is tired from the trip.
5. Someone should break the news to him.
6. I asked my father what an indefinite pronoun was.
7. He asked my mother what an indefinite pronoun was.
8. She was too tired to think of what an indefinite pronoun was.
9. My dogs were no help with indefinite pronouns.
10. Why do you really want sentences with indefinite pronouns?
Do your own homework!