I. Read the sentences and explain the use of Perfect Tenses. Translate the sentences into Russian:

1. Computers have changed the way in which we live.

2. He will have studied some high-level computer languages by next year.

3. By the 1960’s computers had become faster than their predecessors.

4. There are many different types of memory that have been used in computers.

II. Change the following sentences into interrogative and negative forms:

1. Computers have decreased man’s workload.

2. The students had discussed the news by the end of the lesson.

3. He will have finished the work at the term project by the end of November.

4. Today the Internet has entered everyone’s house.

III. Rewrite the sentences in Perfect Tenses using the appropriate adverbs:

1. Computers as we know them today are going through many changes.

2. Integrated circuitry will further change computers.

3. In 1969 the Intel Company pioneered in the development of semiconductor memory chips.

4. Computers change the way in which many kinds of jobs are done.

5. The demand for computer professionals steadily rises from year to year.

IV. Ask as many special questions as you can:

1. Dr. H. Aiken has created the first completely automatic digital computer, Mark I.

2. All the articles on biosensors had been translated by last Friday.

3. The next generation computers will have been produced by the end of 2015.

V. Read and translate the sentences, mind the use of the Perfect Continuous:

1. The printer has been operating for an hour.

2. The demand for computer professionals has been steadily rising.

3. Will she have been writing the report since early morning tomorrow?

4. They have not been producing any information for a few days.

5. She hadn’t been translating an English article for half an hour when she was brought the dictionary.

6. He had been studying the computer keyboard for an hour when the telephone rang.

VI. Choose the correct tense form. Mind the voice of the predicate:

1. It goes without saying that computers (to create) whole new areas of work …

2. In the mid 1940’s the first digital computer (to build).

3. A hybrid computer (to compile) some properties of digital and analog computers.

4. They (to test) the new system for a week?

5. When I called my friend he (to compile) a program.

6. By the 1960’s semiconductors (to replace) vacuum tubes.

7. Microcomputers (to become) the most commonly used type of computers.

8. He (to give) a lecture on information science at 10 o’clock tomorrow.

9. You (to pass) the exam on integrated circuits by 12 o’clock tomorrow?

10. The main memory (to hold) the instructions and data which (to process currently) by the CPU.

11. They (to study) operational systems next term?

12. They (to discuss) different types of printers at 3 o’clock seminar yesterday.

13. She (to read) for her exam on computer languages for 4 hours.

14. It (to forecast), by the end of this decade exceptionally faster and smaller computers (to replace) those in use today.

15. This famous scientist (not to begin) his research in the second half of the 17^th century.