Ex. 27. употребите глаголы, данные в скобках, в present perfect: 1. i (speak) to him about it several times. 2. we (learn) many new words in this course. 3. he (make) that same mistake several times. 4. i (hear) that story before. 5. i am afraid that i (lose) my car keys. ex. 28. употребите глаголы, данные в скобках, в past perfect: 1. i was sure that i (see) the man before. 2. i asked him why he (leave) the party so early. 3. it was clear that he (give) us the wrong address. 4. the teacher corrected the exercises which i (prepare). 5. he knew that he (make) a serious mistake.

Ex. 27. Употребите глаголы, данные в скобках, в Present Perfect:
1.    I have spoken to him about it several times.
2.    We have learnt many new words in this course.
3.    He has made that same mistake several times.
4.    I have heard that story before.
5.    I am afraid that I have lost my car keys.
Ex. 28. Употребите глаголы, данные в скобках, в Past Perfect:
1.    I was sure that I had seen the man before.
2.    I asked him why he had left the party so early.
3.    It was clear that he had given us the wrong address.
4.    The teacher corrected the exercises which I had prepared.
5.    He knew that he had made a serious mistake.