Контрольная работа по английскому языку № 4

для студентов I курса очно-заочного факультета ЛГТУ

всех технических специальностей

Вариант 1

METALS

Today we know more than sixty-five metals, the majority of which are available in large enough quantities to be used in industry. With the increase in the number of metals has come an increase in the number of their alloys. How many alloys there are in the world is difficult to estimate, because their number increases daily, but a moderate estimate gives it as five thousand.

Of all the metals iron remains by far the most important. Absolutely pure iron is rarely prepared except for laboratory purposes. The irons and steels we use are really alloys of iron, carbon and other substances. They can be made elastic, tough, hard, or comparatively soft. We have by no means come to the end of the possibilities of steel. In comparatively recent years the introduction of stainless steels has opened a new field. Indeed, there seems to be no limit to the number of different types of steel that can be produced.

The discovery of steel alloys brought a high demand for certain metals such as tungsten, chromium and vanadium, which previously had been in very moderate use. On the other hand, we have metals that possess valuable properties but which are extremely limited in use because of their rarity in the earth's crust or the difficulty of their production.

Aluminium was almost a laboratory specimen about one hundred years ago, although it is amongst the most abundant elements in the earth's crust. As a result of improved methods of production, it became a comparatively cheap article with increasing uses. The first steps in the development of aviation still further increased the demand.

Aluminium is one of the most remarkable materials of today. It is light and easily worked. It can be rolled into sheets or drawn into wire. It is easily welded and it can be produced as a fine powder. It is an excellent conductor of electricity and heat; it resists the corrosion of many acids and can form a wide variety of alloys with other metals.

Apart from its use in aircraft, it is being increasingly used by the electrical engineering. The substitution of aluminium for copper in a high-voltage cable allows to reduce greatly its weight. Aluminium is non-magnetic, which makes it preferable to steel for certain parts of electrical machinery.

Balloons are coated with special aluminium paint to reduce the absorption of heat from the sun. Lightweight metals show the way to greater speed in transport. This is why aluminium is being extensively used in the new stream­lined trains. It has been calculated that if a giant Atlantic liner could be constructed of lightweight alloys, it would require engines of only 100,000 horse power instead of about 160,000 horse power to maintain the same speed. Scientists believe that in due course aluminium will become more important than iron.

Research results in new materials being discovered, and the "nearly perfect" of yesterday becomes the "not quite good enough" of today. There is little doubt that progress will be still more rapid during the next century. Research is likely to give us alloys in the near future that will entirely substitute for every one of our most modern metallurgical discoveries.

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) With the . . . in the number of metals has come an . . . in the number of their alloys. 2) How many alloys there are in the world is difficult . . . . 3) Of all metals . . . remains by far the most important. 4) Aluminium is one of the most . . . materials of today. 5) The . . . of aluminium for copper in a high-voltage cable allows to reduce greatly its weight. 6) Balloons are . . . with special aluminium paint to reduce the . . . of heat from the sun. 7) . . . results in new materials being discovered.

III.Найдите в тексте и выпишите предложения с глаголом в страдательном залоге. Укажите временную форму глагола. Переведите предложения письменно.

Образец: She was asked to bring the book.

was asked – Past Simple Passive.

Её попросили принести книгу.

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 you (to be) busy, I (to leave) you alone. 2) If I (not to be) busy, I (to go) to the concert. 3) If I (to get) a ticket, I (to go) to the concert. 4) If I (to live) near a wood, I (to gather) a lot of mushrooms. 5) If my father (to return) early, we (to watch) TV together.

V.Раскройте скобки, употребляя глаголы в требуемой форме.

1) I would be delighted if I (to have) such a beautiful fur-coat. 2)If it (to rain), we will have to stay at home. 3) If he (to work) hard, he would have achieved great progress. 4) If it is not too cold, I (not to put) on my coat. 5. I (to write) the composition long ago if you had not disturbed me.

VI.Переведите следующие предложения на английский язык.

1) Если бы она не прислала вчера это письмо, мой брат был бы сейчас дома. 2) Если бы у нас было меньше багажа, мы бы пошли на вокзал пешком. 3) Если бы вы услышали его произведения, вы бы узнали, какой это замечательный композитор. 4) Если бы я был на вашем месте, я бы посоветовался с родителями.