1. I have never eaten caviar.
2. We have not been to Spain yet.
3. She has not written to me since last summer.
4. My friend and I have seen an interesting film recently.
5. They have not had a holiday this year.
6. My elder sister has just come back.
7. My father has already read these magazines.
8. The pupils have not done Exercise 5 yet.
9. His mother has never translated such difficult articles.
10. I have called him several times this week.