1. I don't know this girl. I have never met her before.
2. "Where is Mother?"-"She has just gone out.
3. "Don't you know what the film is about?"-"No, I haven't seen it.
4. Don't worry about the letter. I have already posted it.
5. "Is he a good teacher?"-"Oh yes, he has helped me a lot."
6. I know London perfectly well. I have been there several times.
7. I can't find my umbrella. I think, somebody has taken it by mistake.
8. "Do you speak Spanish?"-"No, I have never studied it.
9. "Do you know where they have gone?"-"No, they have sold their house and haven't left their new address."
1 have never met
2has just gone
3i haven't seen
Have already posted
Has helped
Have been
Has taken
Have never studied
Have sold
Haven't left