1. Alice has been preparing for her exam since 9 o'clock.
2. The weather is awful. It started raining three hours ago and it hasn't stopped yet.
3. Jeremy is exhausted. He has been running for two hours.
4. I am so dirty because I have been painting the fence for several hours.
5. They just have finished doing their homework.
6. Have you ever been to the USA?
7. How long have you been learning French?
8. We have been waiting here for half an hour.
9. I already have seen this film, that's why I don't want to go to the cinema.
10. My parents have been building our new house since 2018.
11. Mary hasn't started her job yet.
12. Jane already has sent seven letters.
13. Sandy has been teaching English for ten years.
14. I can't find my key. I think I have lost it.
15. Dan is so tired. He has been working in the garden the whole morning.
2) more friendly
3) more interactive
4) more expensive
5) tidier
6) fatter
7) smaller
8) more competitive