Пособие состоит из 16 уроков и трех дополнительных разделов. Каждый урок рассчитан на работу в течение 4-5 часов аудиторных занятий

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7.4 Say whether the following statements are true or false 
1. The earth is a spheroid flattened at the poles. 
2. The axis on which the earth rotates is longer by 27 miles than the equatorial
diameter.
3. The hydrosphere includes all bodies of water in liquid state. 
4. The lower boundary of the crust is 20-25 miles beneath the ocean and only about 
4 miles beneath the surface of the continents. 
5. Materials the mantle composed of, are much denser than those making up the 
crust.
6. The temperature of the outer core may be as high as that at the surface of the sun. 
7. All naturally radioactive elements are known to change finally into lead. 
7.5 Fill in the blanks with the suitable words from the text 
1. ………. makes up only 0.02 per cent of the mass of the earth. 
2. ………. is composed of materials much denser than those making up the crust. 
3. The atmosphere, the hydrosphere and the lithosphere are the ………. layers of the
earth. 
4. The earth is not a true ………. but a ………. . 
5. The discovery of ………. gave the scientists a new means of estimating ………. of
the earth. 
6. ………. includes the rocks of the continents as well as the rocks beneath the ocean
floor. 
7. The continents are made up of ………. covered by a thin layer of ……, and
underlain by ………. . 
7.6 Complete the following sentences 
1. Compared with quite an ordinary star, like the sun, the earth ………. . 
2. By measuring the amount of lead present in rocks containing uranium we can 
………. . 
3. The atmosphere, the outermost layer, is ………. .
4. The floor of the ocean basins is mostly underlain by………. . 
5. The mantle is believed to consist of ………. . 
6. The oldest rock so far discovered has been dated at ………. . 
7. One gram of uranium will yield ………. .
7.7 Translate into English 
1. Атмосфера, гидросфера и литосфера – это внешние оболочки Земли. 
2. Атмосфера – воздушная оболочка Земли, гидросфера – водная оболочка 
Земли, литосфера – земная кора + часть мантии. 

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3. Гидросфера включает воды Мирового Океана, воды суши и воду в атмосфере. 
4. Газы, из которых состоит атмосфера: 78 % азот, 21 % кислород, 1 % другие 
газы. 
5. Земная кора – это твердая оболочка, покрывающая землю. 
6. Земная кора, мантия и внутренняя часть ядра твердые, внешняя часть ядра 
считается жидкой. 
7. Ученые считают, что Земля образовалась около 4.5 миллиардов лет назад. 
7.8 Read and translate the dialogue. Reproduce it 
A: We can easily study the outer layer of the earth but how do scientists form theories 
about the inside of the earth? 
B: Well, theories about the structure of the earth are based on facts. Being unable to 
penetrate into the centre of the earth scientists must collect facts indirectly. Most 
information comes from studying earthquakes. 
A: Perhaps it is the waves caused by earthquakes that are being studied, isn’t it? 
B: Quite right. A record is kept of the intensity, time and direction of the waves send 
from the earthquake centres.
A: Do the waves travel at a uniform speed? 
B: No. It seems that the waves bounce off from certain layers and it is this 
information which shows us that the earth has different layers, that it is not uniform 
from the surface to the core. 
7.9 Answer the following questions 
What are the outer layers of the earth? 
What is atmosphere? hydrosphere? lithosphere? 
What are the three major parts of the earth?
What kinds of materials are the crust and the mantle composed of? 
The core is believed to vary in structure and composition, isn’t it? 
What method has been used to estimate the age of the earth? 
What is the approximate age of the earth? 
7.10 Write down a summarizing sentence for each paragraph of the text “The Earth”. 
On the basis of the above task, prepare an oral summary of the text 

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