4. Summarize the general ideas of the text. Use the following plan:
1. Forms of existence of electrical energy contained in the radio wave.
2. The essential properties of a radio wave.
3. Measuring of the strength of a radio wave.
4. Main characteristics of radio wave travelling.
5. The direction of polarization of the wave.
5. Put the verbs in brackets into the correct form using Passive:
1. This experiment (to insist)________on by our engineers yesterday.
2. Several types of lasers (to develop)_________every year.
3. The apparatus (to check)________at the lab by our engineers next week.
4. Automation (to use widely)________in space research now.
5. While the experiment (to carry out)_________nobody left the lab.
6. Now different types of radio devices (to study)________by a lot of research groups.
7. The apparatus used in our research (to describe)________recently.
8. After a new device (to test)________it was installed in our laboratory.
9. The construction of this television centre (to complete)________by the end of the next year.
10. The information (to base)________on the data received from a computer.
11. A new type of computing equipment (to produce)________at this plant now.
12. This experiment (to carry out)________under low pressure when the engineers decided to change the conditions of the work.
13. lt is well-known fact that the computer must (to take)________ care of.
14. Future engineers (to give)_________practical training at the best laboratories of our institute.
15. This new measuring device (to design)_________by the end of the next year.
16. The engineer (to ask)________to test the apparatus yesterday.
17. A new device for measuring pressure (to design)__________now.
18. Your invention (to speak)________of at the last meeting.
19. The magnetron is a vacuum tube whose current (to influence) _________by a magnetic field.
20. At this time tomorrow a new magnetic gear (to install)________.
21. The new device (to test)________for two hours when the chief engineer came and stopped the experiment.
22. The scientist (to offer)________ new theme for research.
23. Another useful metal is tungsten which (to use widely)________in industry.
24. The engineer was shown a new device which (to construct) _________by the scientists and engineers of their laboratory.
25. A new type of electronic equipment (to give)________much attention to.
6. Choose the appropriate form of the verb:
1. Electronic energy (will exist, exists, had been existing) in the form of electromagnetic waves.
2. These waves (are travelling, travels, travel) with the velocity of light.
3. The essential properties of radio waves (was, were, are) frequency, intensity, direction of travel and plane of polarization.
4. The strength of a radio wave (is measured, will be measured, has been measured) in terms of the voltage stress produced in space by the electrostatic field.
5. The wave always (had traveled, travels, is travelling) in a direction at right angles to the wave front.
6. A plane parallel to the mutually perpendicular lines of electrostatic and electromagnetic flux (is called, is being called, calls) the wave front.
7. If the direction of either the magnetic or electrostatic flux is reversed, the direction of travel (had been reversed, is reversed, was reversed).
8. The direction of the electrostatic lines of flux (is calling, will call, is called) the direction of polarization of the wave.
9. If the electrostatic flux lines are vertical the wave (is, was, were) vertically polarized.
10. When the electrostatic flux lines (were, will be, are) horizontal and the electromagnetic flux lines are vertical, the wave (was, is, has been) horizontally polarized.