Answer:
1. He left quite early but he hasn't arrived yet.
2. We haven't seen each other since we left school.
3. Have you ever written a poem?
4. She has never been to Istanbul.
5. I loaned him £50 last week, but he hasn't paid me back yet.
6. I don't see them often but I've known them for ten years.
7. What year did you leave school?
8. We're lost. We have already been down this road twice.
9. I sent her an email last week, but she hasn't replied yet.
10. They've lived in that house since 1980.
Explanation:
