В. Н. Бгашев е. Ю. Долматовская английский язык для студентов машиностроительных специальностей учебник
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Переведите заголовок текста. Какую информацию вы ожидаете найти в тексте? Прочитайте текст и скажите: а) в каком абзаце говорится о подразделении всех металлов на два типа; б) о каких неметаллах упоминается в тексте. TEXT A. ENGINEERING MATERIALS Engineers have to know the best and most economical materials to use. Engineers must also understand the properties of these materials and how they can be worked. There are two kinds of materials used in engineering — metals and non-metals. We can divide metals into ferrous and non-ferrous. The former contain iron and the latter do not contain iron. Cast iron and steel, which are both alloys, or mixtures of iron and carbon, are the two most important ferrous metals. Steel contains a smaller proportion of carbon than cast iron. Certain elements can improve the properties of steel and are therefore added to it. For example, chromium may be included to resist corrosion and tungsten to increase hardness. Aluminium, copper, and the alloys (bronze and brass) are common non-ferrous metals. Plastics and ceramics are non-metals; however, plastics may be machined like metals. Plastics are classified into two types — thermoplastics and thermosets. Thermoplastics can be shaped and reshaped by heat and pressure but thermosets cannot be reshaped because they undergo chemical changes as they harden. Ceramics are often employed by engineers when materials which can withstand high temperatures are needed. TEXT-BASED ASSIGNMENTS LANGUAGE STUDY Прочитайте текст снова и выпишите из него активные слова и словосочетания: а) существительные, обозначающие различные материалы; б) словосочетания, используемые при классификации объектов; в) глаголы и глагольные сочетания, дающие характеристику материалам. Замените выделенные слова и словосочетания словами и словосочетаниями из текста. Model: There are two kinds of engineering materials. There are two kinds of materials used in engineering. Nickel steel is a mixture of iron, carbon and nickel. 2. Chromium can be added to steel to provide a good cutting edge. 3. There are many kinds of steel used in industry. 4. Ceramics are used by engineers where heat-resistant materials are needed. 5. Chromium steels resist corrosion. а) Найдите в тексте предложения, построенные по модели can, may, must/have (has) to + V, и переведите их. б) Определите, какие из высказываний соответствуют содержанию текста. Engineers must know the properties of engineering materials. 2. All materials can be classified as metals and non-metals. 3. Non-ferrous metals can contain iron. 4. Steels have to contain more carbon than cast iron. 5. Ceramics can resist high temperatures. 6. Thermosets may be machined. 7. Thermoplastics can be shaped and reshaped. Соедините пары предложений, используя: however — однако, therefore — следовательно, because — так как. Следуйте образцам: Model 1 Copper does not rust. Copper corrodes. (a + b) Copper does not rust; however it corrodes. Model 2 Cast iron is a brittle metal. Cast iron is not used to withstand impact loads. (a + b) Cast iron is a brittle metal, therefore it is not used to withstand impact loads. Model 3 Titanium is used for aircraft frames. Titanium is light and strong. (a + b) Titanium is used for aircraft frames because it is light and strong. Chromium resists corrosion. Chromium is added to steels to make them rust-proof. 2. Manganese steel is very hard. Manganese steel is used for armour plate. 3. Bronze has a low coefficient of friction. Bronze is used to make bearings. 4. Nylon is used to make fibres and gears. Nylon is tough and has a low coefficient of friction. 5. Tin is used to coat other metals to protect them. Tin resists corrosion. 6. Tin is expensive. The coats of tin applied to other metals are very thin. 7. Stainless steels require little maintenance and have a high strength. Stainless steels are expensive and difficult to machine at high speeds. 8. Nickel, cobalt and chromium improve the properties of metals. Nickel, cobalt and chromium are added to steels. Соедините следующие предложения в одно сложное предложение с помощью данных коннекторов. Вы можете опускать слова и делать любые перестановки, необходимые для сохранения английской модели предложения. Model: because/and/however Plastics are used widely in engineering. They are cheap. They have a resistance to atmospheric corrosion. Plastics are not particularly strong. Plastics are used widely in engineering because they are cheap and have a resistance to atmospheric corrosion; however, they are not particularly strong. and\ There are two types of plastics. Thermoplastics are plastics. Thermosets are plastics. and I whereas / and\ Thermoplastics will soften when heated. Thermoplastics will harden when'cooled. Thermosets set on heating. Thermosets will not remelt. from/to: Plastics are used to make a great variety of products. Plastics are used to make textiles. Plastics are used to make engineering components. such as: Plastics are available in many forms. Plastics are available in the form of sheets, tubes, rods, moulding powders and resins. to: Various methods are used. These methods convert raw plastic into finished products. Compression moulding is a common method. Compression moulding is used for shaping thermosets. with/which: The equipment consists of a press. The press has two heated platens. The two heated platens carry an upper and a lower mould. then: Powder is placed in the lower mould. This is moulding powder. The upper mould is pressed down on the lower mould. to/which: The pressure and the heat change the powder. The powder becomes liquid plastic. The liquid plastic fills the space between the moulds. when/and: The chemical changes have taken place. The mould is opened. The moulding is extracted. by: Plastic bowls are made. The compression moulding method is used. Найдите в последнем абзаце текста сложные предложения и объясните логику их построения, ориентируясь на коннекторы. Переведите последнее предложение абзаца на русский язык. Запомните значения следующих компонентов сложных слов: -tight — характеризует качество соединения -proof, -resistant — характеризуют свойства материалов. Например: an air-tight connection — a connection which air cannot pass through a heat-resistant material — a material which is not damaged by heat a moisture-proof coating — a coating which moisture cannot pass through an acid-proof cement — a cement which is not damaged by acid Переведите следующие сочетания. a gas-tight seal, an oil-proof cement, a water-resistant grease, a lightproof coating, a water-tight connection, a sound-proof engine cladding, a rust-proof surface, a shock-proof mounting, a corrosion-resistant steel, a weather-proof surface Найдите в первом абзаце текста прилагательные, обозначающие превосходную степень качества, и дайте исходные формы этих прилагательных. Найдите в этом же абзаце слова-заместители и укажите, какие слова из текста они замещают. Найдите в тексте предложения, в которых говорится о классификации материалов, и переведите их на русский язык. Пользуйтесь таблицей на с. 129.
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