III. Употребите возвратные местоимения. l.You said it 2. Go and wash

l.You said it... 2. Go and wash.... Ann! 3. I saw him... 4. The play... was not interesting. 5. They want to do it... 6. She doesn't like to speak about....

V. Образуйте от глаголов причастие II, переведите словосочетания на русский язык

Houses (to build) - built houses, a (to break) device, a (to apply) load, rockets (to launch), an object (to observe), experiments (to make)

V. Переведите предложения, обращая внимание на видовременные формы страдательного

залога.

. The meter rule is divided into 100 centimeters. 2.This experiment was performed by first-year students.

. All questions will be answered at the next lesson. 4. Distance is usually measured in millimeters,;entimeters, metres or kilometers. 5. The photoelectric effect was discovered by Heinrich hertz in 1887. 6. scientific exhibition will be opened soon.

'I. Перепишите предложения, обратите внимание на придаточные предложения; переведите их на русекий язык.

. We shall not begin until you come. 2. If the weather were fine, he would go to the country. 3. If had Iknown her address, 1 should have congratulated her on birthday. 4.1 wish it were spring now. 5. Don't worry if I am late tonight. 6. If he went to bed now, he wouldn't sleep.

JVII. Прочитайте текст, переведите его письменно и ответьте на вопросы после текста.

Metals

Metals are materials most widely used in industry because of their properties. The study of the production and properties of metals is known as metallurgy.

Most metals are dense, because the separations between atoms in them are small. The atoms are arranged regularly and can slide over each other. That is why metals are malleable (can be deformed and bent without fracture) and ductile (can be drawn into wire). Metals vary greatly in their properties. For example, lead is soft and can be bent by hand, while iron can only be worked by hammering at red heal. 'The regular arrangement of atoms in metals gives them a crystalline structure. Irregular crystals are called grains.

The properties of the metals depend on the size, shape, orientation, and composition of these grains. In general, a metal with small grains will be harder and stronger than one with coarse grains. Heat treatment controls the nature of the grains and their size in the metal. Small amounts of other metals (less than 1 per cent) are often added to a pure metal. This is called alloying (легирование) and changes I the grain structure and properties of metals.

.Drawing, rolling, hammering and extrusion can form all metals, but some require hot working. Metals are subject to metal fatigue and to creep (the slow increase in length under stress) causing deformation and failure. Kngineers when designing, for example, airplanes, gas turbines, and pressure vessels for high-temperature chemical processes take both effects into account. Metals can be worked using machine tools.

The ways of working a metal depend on its properties. Many metals can be melted and cast in moulds, but special conditions are required for metals that react with air.

WoriUist

arrangement

coarse

to draw

lead

to hammer

extrusion

rolling

metal fatigue

creep

расположение

грубый, крупный

волочить, тянуть

свинец

ковать

экструзия

прокатка

усталость металла

ползучесть

to slide скользить

vessel сосуд, котел

to cast отливать

mould форма (для отливки)

Дата добавления: 2015-07-20