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."

Verified answer

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