3. Answer the questions:

1. What kind of joining does welding provide?

2. What type of welding can replace arc welding?

3. What is the advantage of laser welding?

4. What metals is plasma arc welding efficient for?

5. Where is the process of plasma arc welding used?

4. Read and retell the humorous story: The absent-minded scientist – Рассеянный учёный.

Many stories are told about Newton’s absent-mindedness. Here is one of them.

One day Newton was thinking about his work. His servant entered his study. She brought an egg which she wanted to boil on a lamp in his presence (в его присутствии). Newton who wanted to be left alone, told her he would boil the egg himself. The servant put the egg on the table beside Newton’s watch and asked Newton not to leave the egg in the boiling water more than two minutes and a half. Imagine her astonishment (удивление) when on her return she found Newton standing in front of the lamp looking attentively at the egg which he held in his hand, while the watch was being in the kettle over the lamp.

Lesson seven Text 1: If there were no electricity

I. Translate this text without using a dictionary:

At present it is difficult even to imagine the time when there was no electricity, when people had to do without it.

What would our everyday life be like if there were no electricity?

Can you imagine a situation when all devices producing electricity would stop?

If this happened in the evening while you were in the cinema, you would be sitting in the dark without light. Then you would walk along dark streets. You would try to take a trolley-bus or a tram, it would be impossible. As there would be no light at home, you should use either a smoking kerosene lamp or a candle.

You would like to use the telephone or watch the TV, but they would not work, because they both depend upon the electric current. This example shows the importance of electricity in man’s everyday life.

II. Match English equivalents with the Russian ones:

while to show device current to have to to happen without light to use either … or to imagine candle importance to depend on along

ток важность, значение свеча в то время как, пока или … или зависеть от устройство, прибор представлять себе показывать вдоль, по приходиться, быть вынужденным использовать свет без происходить, случаться

III. Is electricity really necessary in our life? Why? Give its advantages and disadvantages.

IV. Study adverb-building suffixes:

-ly: rapidly (быстро)

-ward(s): towards (по направлению), forward (вперёд)

Form adverbs from the words given below:

Continuous, wide, east, home, quick, slow, particular, secure, complete, practical, actual, original, special, comfortable, real, part.

Text 2: Energy

V. Read and translate:

What is energy? Scientists would say that energy is the ability to do work. You use energy when you walk. You carry books to the Institute. It takes energy to carry books. You can do nothing without using energy. You put on clothes washed and ironed with energy.

There are many forms of energy. Each of these is useful to us. For example, we use heat energy to do a lot of useful things, namely, to heat our homes, to transport us from one place to another, and so on. Automobiles, trams, trains and airplanes are moved by changing heat energy to other forms of energy.

Electrical energy does many things for us. It is changed to other forms, such as: light, mechanical, heat, chemical, and others. When you watch television, you hear the sound and see the picture. The TV set gets warm. Thus, electrical energy changes to heat, light, and sound.

Many machines use electrical energy. They change energy from one form to another. Devices that are operated with electrical energy help us to work. Indeed, electricity plays an important part in modern life.

ability to use useful to move to change device to be operated

способность использовать полезный двигать, перемещать менять, изменять устройство работать, управляться, обслуживаться

VI. Answer the questions:

1. What is the difference between energy and electricity? 2. How do scientists determine energy? 3. Do you use energy when working on computer? 4. Can electrical energy change to other forms? Can you give examples? 5. Why do we need energy?

VII. Form words with the same root:

Energy, wash, electricity, change, important, light, heat, use, move, science, able, operate, help.

VIII. Find the odd word in each line and explain why:

1. a) sound, b) picture, c) light, d) energy;

2. a) machine, b) automobile, c) train, d) airplane;

3. a) important, b) warm, c) convenient, d) useful;

4. a) watch, b) hear, c) change, d) see;

5. a) thing, b) clothes, c) workpiece, d) transformer;

6. a) electrical, b) heat, c) mechanical, d) chemical;

7. a) to operate, b) to use, c) to help, d) to work.

IX. Read and retell the following story:

The Sun and the Moon

Two men were arguing one day about the sun and the moon and which of the two was more useful. At last one of them said, “Oh! I know. The moon is quite worth two suns, for it shines at night when it is needed, but the sun shines in the daytime when nobody wants it.”