55.3 Finish these sentences with ... friend(s) of mine / yours etc.

55.3 Finish these sentences with ... friend(s) of mine / yours etc.

1. I went to the cinema with a friend of mine.
2. They went on holiday with some friends of theirs.
3. She's going out with a friend.
4. We had dinner with some.
5. I played tennis with a.
6. He's going to meet a.
7. Do you know that man? Is he a.