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1. Read and translate the text:

The term 'semiconductor' means half-conductor that is a material whose conductivity ranges between that of conductors and non-conductors or insulators. They include great variety of elements (silicon, germanium, selenium, phosphorus and others), many chemical compounds (oxides, sulphides) as well as numerous ores and minerals.

While the conductivity of metals is very little influenced by temperature, conductivity of semiconductors sharply increases with heating and falls with cooling. This dependence has opened great prospects for employing semiconductors in measuring techniques.

Light as well as heat, increases the conductivity of semiconducting materials, this principle being used in creating photo resistances. It is also widely applied for switching on engines, for counting on conveyer belts, a well as various systems of emergency signals and for reproducing sound in cinematography. Besides reacting to light, semiconductors react to all kinds of radiations and they are therefore employing in designing electronic counters.

Engineers and physicists turned their attention to semiconductors more that fifty years ago, seeing in them the way of solving complicated engineering problems. Converting heat into electricity without using boilers or other machines was one of them. This could be done as means of metal thermocouples, but in this way impossible to convert more one per cent of the heat into electricity. The thermocouples made later of conductors more generated ten times as much electricity as the metal ones.

Sunlight like heat can feed our electric circuit. Photocells made of semiconducting materials are capable of transforming ten per cent of sunray energy into electric power. By burning wood, which has accumulated the same amount of solar energy, we obtained only heat fractions of one per cent of electric power. The electricity generated by semiconductor thermocouples can produce not only heat but also cold, this principle being used in manufacturing refrigerators. Semiconducting materials are also excellent means of maintaining a constant temperature irrespective of the surrounding temperature changes. The latter can vary over a wide range, for example, from 59C below OC to 100C above OC. Semiconductors are the youngest field of physical science. Yet even now they are determining the process of radio engineering, automation, chemistry, electrical engineering and many other fields of science and technique.

2. Read and translate the text in a written form:

Electronic devices are used in every sector of the modern economy. The industry employs over a million people in developing, manufacturing, and selling electronic equipment and devices. About 34 percent of all workers in this field work for companies that make electronic components, such as semiconductors, electronic coils, and transformers or electronic connectors. Computers, communications equipment, navigational systems, and other electronic equipment are sold to the government, businesses, and industries to be used in transportation and data processing and in automated production systems. Television sets, digital cameras, wireless telephones, and personal computers are some of the many electronic products sold to consumers.

The largest group of workers in the electronics industry have formal training in a variety of technical and professional areas. Before an electronic product can be manufactured and offered for sale, a good deal of work goes into research and development. Much of this research is done by scientists, including physicists, chemists, and mathematicians. Engineers apply the scientific research to specific production problems. Electrical engineers make up the largest group of engineers in the industry, but the field also employs mechanical, chemical, and metallurgical engineers. Working with engineers and managers, industrial designers determine what a product will look like. The largest segment of the industry's professional and technical workers consists of computer specialists, who work in areas from the design of new products to programming the computers that control automated manufacturing processes. Other technical workers, such as electronics technicians, drafters, and engineering aides, also assist the scientists, engineers, and designers. About 31 percent of all workers in electronics manufacturing have plant jobs in production, maintenance, and related areas. The largest group of employees consists of assemblers who put together components and finished products. Assemblers usually use small tools, soldering irons, and light welding equipment and follow printed diagrams or instructions. Less-skilled assemblers perform repetitive tasks on assembly lines that require manual dexterity. As more and more assembly processes are automated, assemblers often supervise the machinery that does the actual assembly of products.

Other workers in the industry process parts or get them ready for assembly. Tinners and electroplaters, for example, coat metal or plastic parts with a thin coating of metal. Anodizers treat these parts in special baths that leave a protective or decorative film. Silkscreen printers place decorative patterns or instructive diagrams on electronic equipment. Etching equipment operators sometimes etch copper on circuit boards. Other special workers employed in the electronics industry include operators of infrared ovens and hydrogen furnaces, who remove any moisture or foreign matter left on glass, ceramic, or metal parts. Exhaust operators and sealers tend gas flame machines that remove impurities from tubes, take out the gases, and seal up the tubes. Electronic assembly inspectors check the products after they have assembled them to make sure the products meet the company's standards. Some inspectors are experienced electronics technicians, while others are less-skilled workers. Inspectors and testers are needed at all phases of electronics manufacturing. Maintenance workers, such as industrial machinery repairers and electricians, repair and maintain manufacturing and electrical equipment. In addition, air conditioning and refrigeration mechanics are needed to maintain the special temperature-controlled, dust-free rooms found in many electronics plants.

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