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1. The building of the trade centre (begin) a month ago.
2. You (see) Nick today? — Yes, but he already (leave).
3. By next year he (write) the novel for three years.
4. He (leave) for Canada two years ago and I (not see) him since.
5. Don't come in, he (take) an exam. He (take) his exam for half an hour already.
6. When he (come) into the office the secretary (do) a crosswords puzzle.
7. Mother (cook) dinner before he (come).
8. I'm leaving now, but I suppose I (see) you in the evening.
9. The committee (prepare) the plan by tomorrow.
10. He (do) everything already? — Yes, he (do) his part of work long ago.
11. Be quiet, please. We (work) at the translation and you (make) a lot of noise.
12. He always (go) for a walk in the evening.
13. We (talk) about Jim when he (run) into the room.
14. She (write) this exercise yesterday at 8 o'clock.
15. They (learn) the new words yesterday from three till seven.
16. Не (finish) the first part of his book and now he (write) the second. He (work) at his book for two years.
17. She (have) a bath at seven o'clock last night.
18. Linda also (answer) telephone calls, sometimes she (show) visitors around the factory.
19. The library (close) by the time I (get) there.
20. She (look) at him while he (read) a newspaper.
21. Hurry up, Jane! We all (wait) for you.
22. The scientists (carry) out many experiments before they (achieve) satisfactory results.