15. is washing/ has just repaired

16. Have you been/ spent

17. have never met/ looks

18. will be/ comes

19. found/ has just left

20. arrive/ will probably be raining

21. is raining/ stops

22. were watching/ failed

23. stayed/ has lived

24. sat/ were being repaired

25. turned/ went/ had forgot

26. has changed/ came

Xin hay nhất ạ

15. David is washing his hands. He have just repaired the TV set.

16. Have you been here before? Yes, I spent my holidays here last year.

17. We have never met him. We don't know what he looks like.

18. The car will be ready for him by the time he comes tomorrow.

19. On arriving at home I found that she have just left a few minutes before.

20. When we arrive in London tonight, it will probably be raining.

21. It is raining hard. We can't do anything until it stops.

22. Last night we were watching TV when the power failed.

23. That evening we stayed up to talk about the town where he had lived for some years.

24. I sat down for a rest while the shoes were being repaired.

25. Half way to the office Paul turned round and went back home because he forgot to turn the gas off.

26. London has changed a lot since we first came to live here.