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Finding a Fault in the Car
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If your car doesn't start in the morning, you should check three things first: the battery, the fuel level and the spark plugs. It is easy to repair these faults. If the battery is flat, you should recharge it. If this doesn't work, you should replace it. If the petrol tank is empty, fill it up. If the spark plugs are dirty, clean them, and if the gap in a spark plug is too narrow or too wide, adjust it to the correct width.
Section 12
1.Прочтите текст с целью общего понимания содержания.
2.Ответьте на вопросы, помещенные после текста.
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Let's look closer at the engine components that operate together to generate power. The basic unit of the engine is the piston which moves up and down inside a cylinder. As air is compressed in the cylinder, fuel is injected on top of the piston. Under high pressure the fuel mixes with the hot air end self-ignites causing combustion. The force of the combustion pushes the piston and connecting rod down turning the crankshaft and flywheel which drive other components.
During engine operation the piston goes through four strokes: intake, compression, power and exhaust. During the four strokes, the piston moves down and up to complete cycles.
Intake: During the intake stroke the piston moves down in the cylinder pulling air past an open intake valve into the combustion chamber.
Compression: During the compression stroke all valves are closed, and piston moves up in the cylinder compressing the air. As the air molecules are compressed the air temperature increases dramatically to about 1000° F (537° C). As the piston nears the top of its stroke, fuel is injected into the combustion chamber on top of the piston. The fuel mixes with the hot compressed air and causes combustion.
Power: During the power stroke the valves are closed as the forces from combustion push the piston and connecting rod down, thereby turning the crankshaft. The heat energy has now been converted into mechanical power.
Exhaust: During the exhaust stroke the inertial force of the turning flywheel helps continue the rotation of the crankshaft to push the piston up again in the cylinder forcing the burned gases out the open exhaust valve. This completes the four strokes of the piston. These four strokes are repeated over and over as the engine operates.
Diesel engine offers the following advantages over automotive-type gasoline engines:
Fuel economy
Diesel engines have higher compression ratios and therefore burn fuel more completely and efficiently.
Reliability
Diesel engines have no electrical ignition system to fail or be maintained. They are built with heavy-duty parts to withstand the higher compression ratios and to operate for long periods with minimum breakdown. In on-highway trucks for instance, diesel engines have a projected service life of many hundreds of thousands of miles.
Power
It depends on engine size, but diesel engines generally produce more torque and power output than gasoline engines.
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QUESTIONS
1.What takes place in the combustion chamber during the intake stroke?
2.What takes place in the cylinder during the compression stroke?
3.What takes place in the combustion chamber during the power stroke?
4.What takes place in the combustion chamber during the exhaust stroke?
5.What advantages do diesel engines offer?
Section 13
Прочтите текст с целью общего понимания содержания.
Напишите, что делается для того, чтобы сократить потери отработанного газа.
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The Саr and the Environment
Most of us know that cars cause air pollution. Scientists tell us that if we don't do something soon, we will be unable to repair the damage that we are causing to our planet. What are some of the things we can do to help?
Buy a fuel-efficient car and keep it that way
Good gas is a way to stop pollution. Choose a car that is friendly to the environment when you buy one.
Keep your car tuned up
A car that badly tuned releases more pollutants into the air. If you keep track of your gas mileage, you'll know when something is wrong. A badly tuned car uses almost 10% more gas than a well-tuned car. Other ways to waste gas are:
Idling your car unnecessarily. If you are stopped for longer than a minute, it is more fuel efficient to turn off your engine.
Using dirty fuel filters. Dirty fuel filters waste gas.
Air Conditioner Maintenance. Of course, this causes a big problem for both us and our mechanics. Our mechanics will have to make sure that there are no leaks, and fix them if there are, before they can add any R-12 (freon) to our air conditioning systems. Naturally, this cost will be passed along to us.
Section 14
1.Прочтите текст с целью общего понимания содержания.
Найдите в тексте предложения, в которых говорится о том, чего не следует делать.
Кратко перечислите, что необходимо предпринять для улучшения экологических условий.
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Gas Ecology
There are many ways that we can reduce pollution by observing good gas ecology — that is using our cars in fuel efficient ways.
Don't move the car unless you are going somewhere. Plan ahead. Starting the car up just to move it a short distance produces more pollutants than hours of driving on the freeway.
Don't use your heater until the car is warmed up. The engine will start more quickly, because it won't be losing heat to warm you.
Try to drive within 35-45 miles per hour when possible. Driving at slower speeds reduces engine efficiency and causes more pollutants.
Don't make fast starts or stops. Fast starts can burn more than 50% gas than regular acceleration (as well as cause 50% more emissions). When a big burst of gas enters the engine, much of catalytic converter's job is bypassed and the unburned gas comes out the tailpipe or is sent into the converter. Rapid acceleration is only called for in emergency or passing situations. Stopping rapidly also leaves the engine with a lot of unburned gas to deal with. This results in damage to the converter and pollution.
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Try not to idle. At bank lines and fast food places with over thirty second waits, turn the engine off, and restart it. It is more fuel efficient, and causes less pollution. The only time that idling is a good thing is after a long, fast run. Idling the engine for a minute or so after one of these helps get rid of any hot spots and fuel vapors.
Keep to steady speeds on the highway. Changing speeds produces more pollution and uses more gas. Don't use the air conditioner unless you have to. It makes your engine work harder, uses more gas, and causes more pollution. Most evaporative emissions get into the atmosphere when we put gas in our cars. Make sure your gas cap is the right one, and in good working order. Gas caps don't cost that much, but are very important in anti-pollution.
Since gasoline expands, never overfill your tank. It will wind up leaking out.
Use known brands of gas. Poor quality gas will not save you money. Instead, it will foul your engine and cause it to function badly. Try several different brands and octane ratings to find out which makes you car the happiest, and stay with it.
Section 15
1.Прочтите текст с целью общего понимания содержания.
2.Найдите в тексте абзац, в котором идет речь о типах столкновений.
3.Какова основная функция ремней безопасности?
4.Каковы основные правила поведения пешеходов при пересечении проезжей части улицы?
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Road Safety
Every year several thousand people are lolled on the roads. Every year hundred thousand people are injured. These people are killed and injured in road accidents.
Accidents are often caused by carelessness of the people. There are rules that help to make the roads safe, but people do not follow the rules.
In our country as in most other countries traffic keeps to the right, but in Great Britain traffic keeps to the left. While driving the car you can get into trouble. The data indicate that in road accidents the passengers who use different kinds of safety belts suffer from the impacts less than the passengers who don't use ones. It was shown that safety belts had reduced the risk of serious injuries.
Accidents can be divided into three types as follows:
1.Head-on impacts between cars;
2.Side impacts caused by accidents at intersections;
3.Rear impacts in which the car (often stationary) is struck from the rear by another car.
Head-on accidents are the most numerous in which the driver and the front seat passenger suffer head injuries. That is why the most important function of safety belts is to protect the driver and passenger from head injury.
In up-to-date cars various types of safety cushions are used to protect the lives of those sitting in the car. But the gold rule is to be careful on the road while driving the car.
As far as the pedestrians are concerned they should obey the following rules: before crossing the road, stop and look both ways. Look right, look left, and then look right again. If the road is clear, it is safe to cross it.
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