Завдання 1.

Визначте частину мови і значення слідуючих слів без словника:

1. to move, movement, movable, unmovable, to move away, to move up, to move down, to move off.

2. to ignite, ignition, ignitable.

3. direct, direction, director, to direct.

4. electrical, electrically, electricity, electrify.

Завдання 2.

Прочитайте речення, перекладіть їх, поставивши дієслова в дужках у пасивний стан:

1. Each stroke (to accomplish) by one-half of a crankshaft revolution.

2. When the valves (to close) the fuel air mixture (to compress) by the upward stroke of the piston toward top dead centre.

3. The piston moves upward to the top dead centre after its work (to finish).

4. The path covered between top dead centre and bottom dead centre and vice versa (to call) a stroke.

TEXT 3-A.

FOUR-STROKE CYCLE.

In case of the four-stroke cycle engine, the path covered between top dead centre and bottom dead centre and vice versa is a stroke. Each stroke is accomplished by one-half of a crankshaft revolution. The complete cycle requires the following four strokes.

Suction stroke: the piston moving downward takes in fuel-air mixture through the open intake valve, while the exhaust valve is closed. Immediately after the piston has reached the bottom dead centre, the intake valve is closed. The first stroke has been finished. The crankshaft has turned one-half of a revolution.

Compression stroke: with the valves closed the fuel-air mixture is compressed by the upward stroke of the piston toward the top dead centre. The crankshaft has turned one full revolution.

Power stroke: before the piston has reached the upper dead centre, ignition is performed. The compressed fuel-air mixture burns, the gases expand due to the heat of combustion and force the piston downward. The valves are still closed. The crankshaft has turned one and one-half of a revolution.

Exhaust stroke: after its work has been finished the piston moves upward to the top dead centre and pushes the burned gases out of the cylinder through the open exhaust valve. As soon as the piston has reached the top dead centre, the exhaust valve is closed and the intake valve is opened. Now the crankshaft has completed two revolutions. The next cycle can begin.

Підберіть до слів лівого стовпчика слова з правого стовпчика:

to complete the bottom dead centre

to push the piston downward

to reach the suction stroke

to force the gas outward of the cylinder

Завдання 3.

Дайте відповідь на слідуючі питання:

1. What is a stroke?

2. How many strokes does a cylinder consist of?

3. What is the first stroke?

4. Where does the piston move?

5. Is the exhaust valve closed?

6. When is the intake valve closed?

7. What is the second stroke?

8. Are the valves closed?

9. By what stroke of the piston is the fuel-air mixture compressed?

10. What is the third stroke?

11. When is the ignition performed?

12. Due to what does the piston move downward?

13. What is the 4-th stroke?

14. Where does the piston move?

15. Through what do the burned gases go out?