Exercises

/. Translate the following sentences and define the non-finite forms of the verb:

1. Protecting buildings from strokes of lightning was a great achievement in the field of electricity. 2. Speaking of the magnet, the inventor made reference to its property of attracting iron and steel. 3. Experiments showing the changes in substances are very important for industry. 4. The teacher objects to our translating such- an easy text with a dictionary. 5. Soviet people constructed many hydroelectric stations, the one on the Angara being one of the largest. 6. In studying magnetism, we cannot help observing the re- -lation between magnetism and the electric current. 7 Having invented the lightning conductor, Franklin continued work­ing at the problem of atmospheric electricity. 8. The experi­ments having been made, we could discuss the results. 9. The atoms of different substances have different weights, their properties being also different. 10. Having experimented with electricity and magnetism, Gilbert wrote a book on magnetism. 11. Gilbert greatly contributed to the study of magnetism, Galileo taking great interest in Gilbert's achieve­ments.

//. Translate the following questions and answer them:

1. Существует ли связь между электричеством и магне­тизмом? 2. Знаете ли вы, кто открыл магнетизм? 3. Что вы знаете об атмосферном электричестве? 4. Кто доказал, что наша земля является большим магнитом? 5. Что вы знаете о магнетизме? 6. Каковы свойства магнита? 7. Кто интере­совался достижениями Гильберта? 8. Какие опыты прово дил Франклин?

ап*7//. Translate the following sentences paying attention to the mrds in bold type:

1. These electrical devices are very large. Who can help me to carry them to another laboratory? 2. After the experi­ment had been carried out the students carried the devices away. 3. What were the students doing when the teacher came into the classroom? They were doing the exercises. 4. Why can't you do without the thermometer? The temperature of this metal is known. 5. He could not go to the cinema yes­terday. 6. Do not turn the light off, I shall go on working. 7. I see nothing, turn the light on, please. 8. On heating, ice turns into water. 9. Water, in its turn, turns into ice on freez­ing.

IV. Make up a story of Franklin's kite experiment using the following sentences as well as sentences of your own (our sentences are given in a disorderly way):

1. The key was connected to the lower end of the string. 2. The story about Franklin's famous kite is known all over the world. 3. They took some necessary things such as: a kite with a long string, a key, and so on. 4. It was proved that lightning is a discharge of electricity. 5. It was a stormy day. 6. The electricity was conducted from the clouds down the string to the key. 7. The kite was flying high among the clouds. 8. The rain wetted the string. 9. Atmospheric electricity greatly interested Franklin. 10. The rain fell.

V. Define what parts of speech these words are:

application, ability, continuous, use, important, numer­ous, civilization, electric, familiar, reader, widely, useful, powerful, property, certainly

VI. Form two sentences with each of the following words: similar, simple, single

VII. Use the following expressions in sentences of your own:

all over the world; as well as; in this connection; in the form of; needless to say; to pay attention to; on the other hand

VIII. Put two questions to each paragraph of the text and answer them.

^{IX. Compare:}

1. A generator and a motor.

2. Potential energy and kinetic energy.

3. Chemical energy and mechanical energy.

4. A nuclear power station and a steam power station.

X. Describe Fig. 3.

XI. Speak on magnetism.

LESSON SEVEN