Измените предложения в совершенное время: 1. my friend has prepared the report (by last monday). 2. the students have done the exercises (by the end of the lesson). 3. mother has cooked supper (by the time i came home). 4. we have not seen our teacher (before the bell rang). 5. have you done the work (before i called you up)? 6. he has translated the article (by this time yesterday). 7. she has not bought a present for him (when we came to her place).

1. My friend had prepared the report by last Monday.
2. The students had done the exercises by the end of the lesson.
3. Mother had cooked supper by the time I came home.
4. We had not seen our teacher before the bell rang.
5. Had you done the work before I called you up?
6. He had translated the article by this time yesterday.
7. She had not bought a present for him when we came to her place.