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2.Дайте відповідь на запитання:

1. What is metalworking?

2. What are cutting machines tools used for?

3. What is metalworking by non-conventional processes used for?

4. What is in a constant process of improving?

3. Визначте вірне речення чи невірне згідно змісту тексту.

1. Cutting machine tools are used to finish, surfaces, make holes, cut threads, etc.

2. Metalworking equipment in general is in a constant of improving.

3. Metalworking is the act processing plastics from raw stock to achieve shape, size and physical form.

4. Metalworking by conventional processes is used to make small holes, finish surfaces or to machine very hard metals.

5. Operation research, programming, cost accounting and other new methods have introduced scientific and mathematical thinking into metalworking.

4. Перекладіть наступні речення з англійської мови на українську, звертаючи увагу на вживання інфінітиву.

1. We consider the results to be satisfactory.

2. I saw him drive a car.

3. Water is likely to be present on Mars.

4. Не seems to know English well.

5. Many excellent books of English classics are known to be trans­lated and published every year.

5. Перекладіть наступні речення з української мови на англійську, звертаючи увагу на зворот there + be.

1. Скільки вікон у вашій кімнаті? - В ній три вікна.

2. Поштове відділення у кінці вулиці.

3. Чи є поштове відділення на цій вулиці? - Ні.

4. У вашому диктанті немає помилок.

5. Пароплав не вийшов учора з порту,оскільки була буря.

6. Оберіть вірний варіант.

1. It…dark. It is time for children to go home.

a) get b) gets

c) is getting d) getting

2. She …a new jacket today.

a) weared b) wearing

c) is wearing d) was wearing

3. It …dark early in winter.

a) get b) gets

c) is getting d) getting

4. Listen !Somebody …in the next room.

a) sing b) sings

c) is singing d) was singing

5. The picture… me back to my childhood.

a) take b) to take

c) took d) taken

7. Утворіть форми Participle I та Participle II від наступних дієслів.

To buy

To catch

To choose

To live

To smile

ВАРІАНТ 4

1. Прочитайте та перекладіть українською мовою, перепишіть та письмово перекладіть весь текст.

In our everyday life we are usually surrounded by consumer items such as lamps, cars, bicycles, players, etc. that utilize sheet steel or other engineering materials as structural components. Depending on the end use these materials are rolled, stamped or formed in some other manner to develop the desired shape.

The choice of the process which will produce the part is one of the most important aspects in the part design. The designer, therefore, must have a clear understanding of various operations and use them from the point of view of their property advantages.

There are two principal methods of shaping products: 1) by means of tools (machining) and 2) by means of rolls or dies (mechanical working).

Mechanical working, either hot or cold, takes advantage of the most valuable property of metals: their ability to be plastically deformed. Plastic deformation is accompanied by a marked change in mechanical properties. Strength values and ductility are the most sensitive to hot working. Gold-worked metals increase in hardness in proportion to the severity of their deformation.

Sheet steel, bar strips and spe­cial shapes such as tubes, rods, wire, etc. can be easily produ­ced by rolling them through huge mills or drawing through dies that reduce cross-sectional area. The thickness or diameter goes down, the sheet gets longer and the strength goes up. Most of carbon steels are available as cold-rolled products. Increased strength, close dimensional tolerances together with a good surface finish are responsible for their use in a wide area of ap­plications.

Hot-rolled products are cheaper than the cold-rolled because it is easier to form a metal when it is red-hot. Structural components such as beams, heavy plates, angles, bears, tubes or channels are produced only by hot working. The great disadvantages of hot-rolled products are lower strength, poor surface finish and looser dimensional control. Nevertheless, they show good weldability and stability in machining. In fact, these are two important reasons to use hot-rolled products in the machine design.

The extrusion, forging or stamping processes can produce a very wide range of sections both solid and hollow, by cheap and economical methods. Close dimensional tolerances can be maintained thus by the appropriate design of sections many engineering components can by produced with a minimum of machining.