Преобразуйте утвердительные предложения в отрицательные, обращая внимание на форму глагола-сказуемого.
1. He has bought a new bike.
2. I’ve sent a letter to my friend.
3. She has made a very bad mistake.
4. The children have gone to bed.
5. We’ve met our business partners.
6. They have cleaned their rooms.
7. The tourists have visited the National Gallery.
8. The teacher has checked our tests.
9. Harry has broken his car.
10. Mary has seen this film.
11. The programmer had done the work by five o’clock yesterday.
12. She was sure she had met him before.
13. She was late for the lecture as she had overslept.
14. The students had finished writing the test when the class was over.
15. She could go to England as she had received a visa.
16. They will have finished the plans by then.
17. Before his holiday Tom will have spent all his money.
18. I will have cooked dinner by then.
19. You will have learnt over half a thousand words when you finish this English book
20. Fernando will have had his operation by August.