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1. According to her father’s plans Sophia (must) get a sound education. 2. As there were no teachers in Palibino Sophia’s father (must) invite an experienced teacher from St. Petersburg. 3. To cover the school programme Sophia’s teacher (must) instruct her in languages, arithmetic, grammar, literature, geography and history. 4. Sophia (can) speak and write French quite well since her childhood.5. Sophia was a very capable pupil. She (can) write excellent compositions and solve complicated problems in mathematics as well.6.Her teacher didn’t expect that at the age of twelve Sophia (can) suggest a new solution for her determination of the ratio of the diameter of the circle to its circumference. 7. At the age of sixteen Sophia asked her father for permission to go on with her studies in St. Petersburg. “You (must) take private lessons, as women (may not) attend lectures at the University” he said.8.He told her that women (must) obtain special permission from the University authgorities.9.Sophia did get that permission, but still she (may not) take examinations.10.”I (must) go abroad to complete my education”, decided Sophia.
2. Task 3. Explain the word combination “conveyor belts” in details
VARIANT 6
Task 1. Read and translate the text.
METALS AND ALLOYS
In the last years or so, due to the fast development of industry, the need for new metallic materials has enormously increased. Metals practically unheard of before, such as germanium, plutonium and thorium have come to light, taking their place in the electronic and atomic industries. There have also been developed high-temperature alloys for power plants capable of withstanding oxidation and erosion, new ferro-magnetic materials, constructional steels, etc., intended for operating under severe stresses.
Practically speaking, each metal possesses certain distinct combinations of properties, that may be varied for specific engineering applications by alloying it with relatively small amounts of other metals. Before starting to study the basic phenomena which determine the performance of metallic materials, it is advisable to get an idea of what the terms “metal”, ”alloy” and “element” mean.
The term “alloy” is commonly used to describe a material containing more than one chemical element, the properties of the alloy being determined by the properties of the elements it consists of. The term “ pure metal”, on the other hand, is used for materials in which almost all chemical elements but one are eliminated.
The distinction between metals and alloys is immaterial for describing the effects of their chemical composition on forming, such as rolling, forging, pressing, etc. But even small amounts of chemical elements, or impurities, in pure metals used in electronics may affect their performance in the same way as the comparatively large quantities of alloying elements in pure metals used in other fields of engineering.
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| MODERN ENGINEERING | | | Task 2. Put all possible questions to the text. |