Прочитайте текст. In modern times bricks can be made of concrete mortar of burnt clay and of a combi...: ответ на тест 912018 - Английский язык

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In modern times bricks can be made of concrete, mortar, of burnt clay and of a combination of some other substances. For example, different types of clay and shale can be used as raw materials. Accordingly, bricks produced nowadays have different sizes, shapes, colours, and textures. Bricks also vary with the method of fabrication and temperatures of burning. It should be noted that some types of brick, such as, for example, salmon bricks are underburnt and highly porous. Naturally, their strength is extremely poor. This property of salmon brick should be taken into account when choosing brick material for construction. But there exist many other types of brick that are extremely strong and almost glass hard. Between these extremes there lie some other types of brick with different properties. Brick properties are of great importance and should be taken into account while choosing material for construction purposes.
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Different types of clay and shale …