Контрольная работа по английскому языку № 4

для студентов I курса очно-заочного факультета ЛГТУ

всех технических специальностей

Вариант 5

GLASS AND POLYMERS

Glass is no longer a fragile material of limited utility. In recent years scientists have created a number of tough and strong "wonder glasses". Some heat-resistant glasses, for example, can be heated until they are red and then plunged into ice water without breaking. A lead oxide glass is almost as heavy as steel. It remains transparent even when subjected to heavy atomic radiation. Tempered glass, made by heating glass until it begins to soften and then quickly cooling its surface, has the strength of cast iron.

And the strongest and toughest form of glass made today - fiberglass - is stronger than any other material of the same weight, provided its surface is perfect. Fiberglass is now used in various products, including electrical insulation, building insulation, car bodies and so on.

For the future, scientists and men of industry have many ideas that now seem revolutionary. These include phosphorescent glass highways that glow softly at night. Research is continually revealing new facts about the nature and possibilities of glass.

And what are polymers? Among new materials that chemistry has made available to us polymers - high molecular compounds - play a most important part. The foundations of the chemistry of poly­mers have been laid by the discovery of the polymerization reaction made in the 19th century by A. M. Butlerov. The importance of this branch of industry has been constantly increasing ever since. Polymers have been put to many uses including space vehicles. Some of them are used to manufacture electrical insulation materials for machines operating for long periods of time at temperatures of up to 2000°C.

A wonderful polymer material is fluoroplastic. It possesses high resistance to heat and frost. No substance, not even gold or platinum, is as chemically stable. Its coefficient of friction is the lowest known, which means that machines can be made which do not require lubrication.

Research centres of Russia are developing new polymer materials to meet the needs of a variety of industries. Russia has practically inexhaustible sources of raw materials – oil and gas – for the production of new synthetic materials.

I.Прочитайте текст и переведите его на русский язык письменно.

II. Заполните пропуски в предложениях, используя текст, и переведите пропущенные слова на русский язык.

1) Glass is no longer . . . . 2) In resent years scientists have created a number of . . . .

3) Some . . . , for example, can be heated until they are red and then . . . without breaking. 4) . . . , made by heating glass until it begins to soften and then quickly cooling its surface, has . . . . 5) . . . is now used in various products, including electrical insulation, . . ., car bodies and so on. 6) For the future, . . . have many ideas that now seem revolutionary. 7) These include . . . . . . that glow softly at night.

III.Найдите в тексте и выпишите предложения с модальными глаголами. Укажете видовременную форму сказуемого. Переведите предложение письменно.

IV.Раскрывая скобки, напишете каждое предложение три раза, построив условные предложения I, II и III типов.

Образец: If you (to be) free, I (to come) to see you.

If you are free, I will come to see you.

If you were free, I would come to see you.

If you had been free, I would have come to see you.

1) If he (not to come) in time, we (to wait for) him. 2) If you (to put on) your glasses, you (to see) better. 3) If you (not to work) systematically, you (to fail) at the examination. 4) If he (to be) ill, he (not to take) part in the football match. 5) If we (not to have) so much luggage, we (to walk).

V.Раскройте скобки, употребляя глаголы в требуемой форме.

1) If these shoes were not too big for me, I (to buy) them. 2) If she (to return) earlier, she would have been able to see him before he left. 3) If only you had let me know, I (to go) there immediately. 4) My brother would not have missed so many lessons if he (not to hurt) his leg. 5) If you (not to buy) coffee, we shall drink tea.

VI.Переведите следующие предложения на английский язык.

1) Если бы он был здесь, он помог бы нам. 2) Если бы я увидела свою приятельницу завтра, я спросила бы её об этом. 3) Если он здесь, то он, вероятно, работает в библиотеке. 4) Он не простудился бы, если бы одел тёплое пальто. 5) Если бы вы лучше знали грамматику, вы бы не делали столько ошибок в ваших упражнениях.