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1.Подчеркните в предложениях глагол-сказуемое, определите его видовременную форму и залог.

1. For many centuries scientists of the world have been successfully working to uncover still unsolved secrets of nature. Present Perfect Continuous Active.
2. Many automatic devices are being introduced at our plant. Present Continuous Passive.
3. After their arrival from the expedition, they will be studying the results of their observations for several months. Future Continuous Active.
4. I was helped by my friend. Past Simple Passive.
5. He will have been working as an electrician for 20 years by the time he is fifty. Future Perfect Continuous Active.
6. The visible side of the Moon has been studied ever since Galileo invented the telescope. Present Perfect Active.
7. Constructors are building the 150km ring road around St. Petersburg. Present Continuous Active.
8. The expedition will be sent to Central Asia next year. Future Simple Passive.
9. The machine tool measures its production itself. Present Simple Active.

• Steel has been also used successfully in the construction of dams. Present Perfect Passive.

1. На протяжении многих веков ученые мира успешно работают над раскрытием до сих пор неразгаданных тайн природы.
2. На нашем заводе внедряется много автоматических устройств.
3. После приезда из экспедиции несколько месяцев будут изучать результаты своих наблюдений.
4. Мне помог мой друг.
5. К пятидесяти годам он будет работать электриком уже 20 лет.
6. Видимая сторона Луны изучается с тех пор, как Галилей изобрел телескоп.
7. Строители строят 150-километровую кольцевую дорогу вокруг Санкт-Петербурга.
8. Экспедиция будет отправлена в Среднюю Азию в следующем году.
9. Станок сам измеряет свою продукцию.
10. Сталь также успешно используется при строительстве плотин.
11. Прочитайте текст и выполните следующие задания.
12. Выпишите из текста 5 существительных, 5 прилагательных и 5 наречий образованных с помощью словообразовательных суффиксов.

существительные destruction ability purification metallurgist plasticity

прилагательное considerable important insufficient various metallic

наречие approximately usually chemically comparatively generally

2. Выпишите из текста 3 словосочетания модальный глагол или его эквивалент + инфинитив.

is to be found

can be increased

have to pass

3. Подчеркните в тексте 5 сказуемых в страдательном залоге.

Metals in the Service of Man

Let us consider why metals play such a great role in man’s activities. Wood and stone are both older in use, yet to a considerable extent they have been replaced by metals. In spite of the great progress of chemistry and increasing output of plastic materials metals are still used for most of machines, structures and instruments. If there were no metals, no railway, airplane, car, electric motor, turbine or pipeline could operate.

The reason for the increased use of metals is to be found in their characteristic properties. The most important of these properties is their strength or ability to support weight without bending or breaking. Resistance to atmospheric destruction, plasticity and the ability to be formed into desired shapes are remarkable as well. Some metals have also special properties – two of which are the ability to conduct electric current and the ability to be magnetized.

Nowadays we know that over three quarters of existing elements are metals. We know approximately over 80 metals and several thousand alloys.

Most metals are usually found in nature as minerals or ores, where they exist in chemical combinations with other substances. Metallic ores contain metals combined with oxygen, sulphur or other metals.

Ores are usually mined and passed to the metallurgist for refining and purification. The ores are treated by fire or chemically by the process called smelting. Ores have to pass through this very complicated process before pure metals are obtained.

But pure metals are comparatively seldom used because they are rather expensive and their strength is generally insufficient for the purposes of to-day. The most important way in which the strength of metals can be increased is alloying. Alloys are the most important engineering materials. Alloys are obtained by adding various metals or non-metals to the main metallic element.