Answer the questions. 1. What was the very first solid material that man began to use?

EXERCISES

1. What was the very first solid material that man began to use?

2. What did natural ceramics provide man with?

3. Why was ceramics used in a variety of applications?

4. What is a main characteristic of construction of ceramic crystals?

5. Why are ceramic materials so strongly resistant?

6. What are the principal elements in natural clays?

2. Translate the sentences:

1. The reaction of carbon with oxygen is highly exothermic. 2. Up to now chemistry has largely been a matter of taking natural products of the earth and converting them to man’s uses. 3. This element exists in two readily recognizable modifications: crystalline silicon and amorphous silicon. 4. Mercury oxide can be readily decomposed by heat. 5. There are many reactions which precede readily, some even violently, if a trace of water is present. 6. For nearly 2,000 years ago it was believed that all heavy objects fell faster than light ones. 7. One of the properties common to nearly all nuclear radiations are particles in their ability to ionize. 8. Hydrogen readily combines with fluorine and chlorine. 9. In many cases mixtures and compounds are not so readily distinguished. 10. There is hardly any living substance in nature which does not consist of compounds containing oxygen.

Note: hardly-ледве; highly-дуже, надто; largely-головним чином; nearly- майже; readily- легко.

3. Translate the following word combinations:

main industrial products; mainly in industry; primarily ionic; is of prime importance; the very substance; a very good substance; by means of; near the limit; the means of.

4. Find the pairs of synonyms:

because of, to provide, lately, to learn, to explain, due to, to supply, recently, to account for, to find out.

5. Find the pairs of antonyms:

hard, solid, fast, light, dull, difficult, heavy, bright, weak, easy, liquid, slow, soft, strong.

6. Open the brackets using the correct verb form:

1. Last year our plant (produced, produces) many ceramic goods which (are used, were used) widely. 2. At first man (baked, has baked) vessels of clay in the sun. 3. Recently ceramic compounds (are used, have been used) even in making steel. 4. Numerous analyses (have been carried out, had been carried out) before they stated the exact composition of this compound. 5. Now many scientists (are working, work) at the investigation of the new properties of ceramic. 6. Many new discoveries (took place, have taken place) since the last century. 7. Last week they (analyzed, analyze) crystal structure of the new materials by means of X-ray diffraction. 8. For many years considerable work (has been carried out, was carried out) to convert ethylene into motor fuel. 9. Many beautiful articles made of ceramics (provided, provides) man with tools even in ancient time.

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