8. Make the following sentences negative and interrogative and translate them:

1. Some transistors used point contacts.

2. This current varies periodically.

3. They described the procedure of data processing.

4. The current remains at constant voltage.

5. This will depend upon the effects of the electric current.

6. He expressed it in cycles per second.

7. This apparatus will supply the circuit.

8. This transformer reduces the A. C. voltage.

9. Make up all possible kinds of questions:

1. A direct current flows only in one direction.

2. The heating effect of current is independent of the direction of the current.

3. The magnetic field varied with the moving coil current.

4. Wattmeters always contain 2 electrical circuits.

5. We shall briefly consider various kinds of electrical instruments.

10. Translate the sentences, state the tense and the voice of the verbs:

1. The measurement of an electric current is based upon its magnetic or heating effects.

2. The action of thermal ammeters depends upon the heating effect of the current in them.

3. Wattmeters are rarely used in D. C. circuits, because the power in them can be obtained from ammeter and voltmeter readings.

4. The application of this principle will be dealt with later.

5. An instrument which measures the energy consumed in an electric circuit is generally known as a meter.

6. The unit of resistance is defined from relation between the difference of potential and the current that flows in a conductor.

7. These quantities were converted from the physical variables of the problem.

8. The analog computer variables are measured rather than counted on digital computers.

9. Some current transformers consist of an iron core and a secondary winding, and the main current is carried by a straight conductor.

10. If a tube has a trouble, it stops operating or operates badly and should be replaced by another one.

11. To eliminate this counter flow, a third grid was placed between the plate and screen grid and connected to the cathode.

12. The intensity of the beam is controlled by the control grid.

13. The high level of television became possible due to the development of modern means of communication.

14. The new studio unit will be fitted with the most modern transistor devices.

15. Computers will handle large amounts of information accurately and rapidly.

16. Hand operations are replaced by those that require little human assistance.

11. State the tense-forms of the verbs in the following sentences and translate them:

1. Yesterday the students of our group came to help me with mathematics.

2. Our scientists will further develop various kinds of computers.

3. Radio waves are the longest members of the family of electromagnetic waves.

4. Where did the first international conference on radio take place?

5. Modern orbital stations weigh up to 20 tons.

6. If you work much, you will get good results.

7. My friend doesn’t like sports.

8. Will you go to the library tomorrow?

9. When the lectures are over, we will go to the reading hall.

10. We will meet tomorrow at the same place.

11. According to the timetable, the train gets in at half past eight.

12. I left school three years ago.

13. I completely agree to your opinion.

14. You found the lost book, didn’t you?

15. He spoke to me in a very friendly way.

16. Which part of the concert did you like most?

17. It was such a warm day that we decided to go to the river.

18. She speaks English well.

19. Electricity cables stretch over the fields.

20. We will not leave home until you come.

21. She never listens to the advice which I give her.

22. If the water continues to rise, these fields will be under water.

12. Translate the following sentences:

1. He will give you the book when you need it.

2. If we put water into a tube, it will take the shape of the tube.

3. I’ll solve this equation if you help me.

4. Unless it is too late, we will go there.

5. The circle will become an ellipse after you compress it.

6. We shall use this substance in the experiment provided it has the necessary properties.

7. As soon as you return from the lab, we’ll begin our work.

8. I won’t be able to explain this phenomenon if I do not analyse all the data.

9. Your experiment will not give good results until you change the speed of the reaction.

10. My friend will translate the text if you give him your dictionary.

11. I will do it if it is necessary.

12. If he concentrates his attention on his studies, he will pass his exams successfully.

13. Translate the sentences paying attention to the form of the verb in the subordinate clause of time and condition:

1. Як тільки буде включений струм, машина почне працювати.

2. Конденсатор буде накопичувати енергію, якщо він не буде мати ушкоджень.

3. Струм буде проходити крізь ланцюг після того, як джерело струму буде підключено до ланцюга.

14. Say the following sentences in the Past Simple (Active). Don’t forget to make the necessary changes:

Example: He usually has his breakfast at 8 o’clock (yesterday, at 9 o’clock).

Yesterday he had his breakfast at 9 o’clock.

1. John often tells me about his holidays. (yesterday afternoon, his family)

2. The postman usually comes at half past seven. (the day before yesterday, at six)

3. We go to the seaside for a week every August. (last autumn, to the country)

4. She always arrives at the office a few minutes before nine o’clock. (yesterday morning, at nine o’clock)

5. They sometimes go to the theatre. (last month, to the circus)

6. She often writes to her mother. (last week, two letters)

7. He is always at home on Sunday. (last Sunday, at the library)

8. Lessons begin at nine o’clock. (on Monday, at half past nine)

15. Translate the sentences. Pay attention to the verbs in the Passive Voice.

1. Sounds are produced by the vibration of matter.

2. The translation from one language into another is performed by the computers.

3. Waves are carried in all directions from the vibrating body.

4. The first-year students are not taught special subjects.

5. Many problems of great interest are discussed at our seminars.

6. A lot of us were invited to the conference.

7. The methods of radio engineering are now applied in various fields of science and technology.

8. The agreement was signed ten years ago.

9. The research will be carried out over a period of four months.

10. Much attention is given to the development of radio engineering.

11. Lasers are now used for many scientific, medical and industrial purposes.

12. The laboratories of our Institute are equipped with modern devices.

13. The results of these experiments will be published in a scientific journal.

14. The importance of sport is known to everybody.

15. We were provided with the necessary literature.

16. The equations were solved by the machine.

17. The young scientist was invited to take part in the conference.

16. Say the following sentences in the Simple Passive. Use the words in heavy type as the subjects of your sentences.

Example: Scientists use crystals in electronic devices.

Crystals are used by scientists in electronic devices.

1. Scientists developed several types of lasers.

2. I will inform you about the new discovery.

3. Solar batteries generate electricity.

4. The researcher carries out the experiments at high temperatures.

5. You always make the same mistakes.

6. He will bring the book next time.

7. Radio employs electrical energy to transmit sounds, images and signals.

8. The lecturer spoke about the latest works in the sphere of radioelectronics.

9. He showed me the articles from the latest magazine.

10. Mendeleyev presented his table in 1869.

11. New data will support the results of our research.

12. These devices distribute the electric energy.

13. Heat converts ice into water.

14. A. S. Popov invented the first radio receiver.

15. The engineer will check the apparatus in the lab.

16. Their laboratory occupies a separate part of the building.

17. Radio devices perform various communication tasks.

18. We use such devices for amplification of radio signals.