Программа по формированию навыков безопасного поведения на дорогах и улицах «Добрая дорога детства» 2
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Exercise 5. Work in pairs. Ask and answer question about different materials using the following phrases:Can …be recycled? What’s …made of ? Is it light (heavy, soft, tough, fragile…)?HELP: gold, plastic, steel, iron, tin, aluminium, etc.TEXT BALLOYSThe most useful metals are iron, copper and aluminium. However, only small quantities of these metals are employed in their pure form. Most of useful metallic materials are formed from combinations of the above metals, known as alloys. An alloy is a mixture of two or more metals melted together. For making alloys metals are usually mixed in their liquid state. A steel containing some metallic element other than iron and carbon is generally known as “special steel”. These various metals when added to steel in certain percentages, increase the hardness and the toughness of the steel. Exercise 1. Read and analyse the text. Give definitions of: an alloy, special steel, the most useful metals. Exercise 2. Retell the text in English. Exercise 3. Match the materials and the definitions. .
Exercise 4. Complete the following sentences using prepositions from, with, of. 1) Bronze contains significant amounts of copper. 2) Galvanised steel is steel coated ______ zinc. 3) Steel is an alloy derived _________ iron. 4) Pure metals can usually be recovered _______ alloys. 5) To produce stainless steel, iron is mixed ________ other metals. 6) Stainless steel contains quantities ___________ chromium and nickel. 7) Glass tableware contains traces _________ metals, such as lead. 8) When new metal is extracted _________ ore, the costs can be high. Exercise 5., Match the materials and their properties.Materials PropertiesSteel glass aluminium water-resistant abrasion-resistant titanium titanium gold gold plastic plastic corrosion-resistant resistan brittle brittle tough copper rubber silver shock-resistant resistant elastic elastic durable heavy heavy lightweight lightweight thermally thermally stable |
