Контрольная работа № 4

Изучите следующие разделы грамматики по учебнику:

1. Неличные формы глагола : Participle I (Present Participle), Participle II (Past Participle) в функциях определения и обстоятельства. Причастные обороты: зависимый, независимый (самостоятельный), объектный.

2. Герундий (Gerund), простые и сложные формы. Основные способы перевода герундия на русский язык. Герундиальный оборот.

3. Сослагательное наклонение.

4. Три типа условных предложений.

Вариант I

1. Перепишите следующие предложения; подчеркните Participle I и Participle II и установите функции каждого из них, т.е. укажите, является ли оно а) определением, б) обстоятельством, в) частью глагола-сказуемого. Переведите предложения на русский язык.

2. When asked, he answered in the affirmative.

3. The device designed by his brigade was very valuable.

3. Any vibrating object produces a sound.

4. A stroke is the distance which is traveled by the piston in its cylinder.

2. Перепишите и письменно переведите на русский язык следующие предложения. Обратите внимание на перевод зависимого и независимого (самостоятельного) причастных оборотов.

1. The pressure in the boiler lowering, the engineer stopped the engine.

2. The new equipment has just been installed, tests conducted under operating conditions having shown its good qualities.

3. Working with machines, sharp tools, motors one must always be careful.

4. We saw the engines being carefully packed in cases.

3. Перепишите и письменно переведите следующие предложения, содержащие герундий.

1. Reading requires us to think, feel and use our imagination.

2. It's impossible to solve economic problems without using the achievements of the scientific and technological progress.

3. After pouring, the molten metal is allowed to solidify in a mold.

4. We know of Newton’s having developed principles of mechanics.

4. Перепишите предложения и переведите их на русский язык, обращая внимание на особенности перевода глаголов в форме сослагательного наклонения.

1. The engineer is the guiding force behind the machine-tool; without the engineer the machine-tool couldn’t function.

2. We suggested that the boiler should be tested.

3. John wishes he had been a mechanical engineer.

4. Students must work hard lest they should fail at the examination.

5. Перепишите и письменно переведите на русский язык следующие сложные предложения. Обратите внимание на перевод условных предложений.

1. If the oil is overheated, stop the engine.

2. If the air were entirely composed of nitrogen, burning would be impossible.

3. It would have saved you a lot of time if you had prepared for your experiment more carefully.

4. Had he used new materials, the device would have been more reliable.

VI. Прочитайте, перепишите и письменно переведите текст.

The Lathe

The lathe is one of the most useful and versatile (1) machines in industry, and is capable of carrying out many machining operations. The main components of the lathe are the headstock (2) and tailstock (3) at opposite ends of a bed, and a tool-holder (4) between them which holds the cutting tool (5). The toolholder stands on a cross slide (6) which enables it to move across the saddle or carriage as well as along it, depending on the kind of job it is doing. The ordinary centre lathe can accomodate only tool at a time on the toolholder, but a turret lathe is capable of holding five or more tools on the revolving turret. The lathe bed must be very solid to avoid vibrations.

The head-stock incorporates the driving gear (7) and a spindle which holds the workpiece and causes it to rotate. The cutting speed of the tool is an important factor. Tapered centres in the hollow nose of the spindle and of the tailstock hold the work firmly between them. A feed shaft from the headstock drives the toolholder along the saddle, either forwards or backwards, at a fixed and uniform speed. This enables the operator to make accurate cuts and to give the work a good finish (8). Gears between the spindle and the feed shaft control the speed of rotation of the shaft, and the forward or backward movement of the toolholder.

The gear which the operator will select depends on the type of metal which he is cutting and the amount of metal he has to cut off. For a deep or roughing cut (9) the forward movement of the tool should be less than for a finishing cut. Centres are not suitable for every job on the lathe. The operator can replace them by various types of chucks (10), which hold the work between jaws (11), depending on the shape of the work and the particular cutting operation. He will use a chuck, for example, to hold a short piece of work for drilling, boring or screw-cutting (12).

A transverse (13) movement of the tool post across the saddle enables the tool to cut across the face (14) of the workpiece and gives it a flat surface. For screw-cutting, the operator engages the lead screw, a long screwed shaft which runs along in front of the bed and which rotates with the spindle. The lead screw drives the toolholder forwards along the correct speed, and this ensures that the threads on the screw are of exactly the right pitch. The operator can select different gear speeds, or reverse the movement of the carriage and so bring the tool back to its original position.

Lathes are now made with numerical control (for short NC) and with computer. They work automatically according to programs. The unit is called a machining centre.

Пояснения к тексту:

1. versatile – универсальный

2. headstock – шпиндельная бабка, передняя бабка

3. tailstock – задняя бабка

4. toolholder – резцедержатель

5. cutting tool – режущий инструмент, резец

6. cross slide – поперечный суппорт, поперечные салазки

7. gear – зд.: передача

8. finish – отделка

9. roughing cut – обдирка

10. chuck – зажимной патрон

11. jaw – кулачок

12. screw-cutting – нарезка винтов

13. transverse – поперечный

14. face – торец

VII. Письменно ответьте на следующие вопросы к тексту:

1. What are the main components of the lathe?

2. What are the functions of a head-stock and a tail-stock?

3. What does the gear selected depend on?

4. What unit is called a machining centre?