A green house is a building made of glass which is used for keeping warm when th

A green house is a building made of glass whichis used for keeping warm when the outside temperature is low. In a similar waythere are several gases in the atmosphere (mixture of gases that surround theearth) which trap the heat produced by the sun and prevent it from escaping.These gases are known as “greenhouse gases”. and the way in which they trapheat in the atmosphere is called the “greenhouse effect”. This is not simplyair pollution. Most of the main greenhouse gases exist naturally in smallamounts in our atmosphere, and without them the earth would be 30 degreescolder and human life would not exist. In other words, the greenhouse effect isa natural course which is to some degree helpful to us.

The problem is that in the last century and ahalf, we have been putting too many of these gases into the earth’s atmosphereby burning large quantities of coal and oil and by cutting down forest. Therapid increase in greenhouse gases is making the world warmer. The world’stemperature has already gone up by half a degree this century, and the sea levelhas risen by 10 centimetres. If the amount of carbon dioxide in the atmospheredoubles, there will probably be a rise in the earth’s temperature of between I and4℃;. This may seem a small increase,but it would be enough to cause major changes in geography and agriculture.Large areas of the world would be flooded, and some areas would become dry andunable to produce crops. It is important, too, to consider that there may be adelay of about 30 years in the greenhouse effect. This means that we are probablyexperiencing only now the effect of the gases put into the atmosphere beforethe 1960s. Since then, our use of these gases has greatly increased.

1. According to the passage, we can know “greenhouseeffect” means_______.  

A. the way in which gases are used for keepingplants warm

B. a natural course that is to a certain degreeuseful to us

C. the way “greenhouse gases” trap heat on theearth

D. the whole course in which greenhouse gasesprevent heat

2. If there were no greenhouse effect,_______.

A. all plants would not grow on ourplanet        B. soil would reduce thetemperature by 30 degrees

C. man would breathe the cleaner air              D.people couldn’t live in the earth

3. Which of the following is not true?

A. Burning too much coal and oil produces lotsof greenhouse gases.

B. It has become warm on the earth now than inthe past.

C. Gases put into the atmosphere now will affectthe earth years later.

D. The temperature in a greenhouse is as high asthat in the atmosphere.

4. Suppose the earth’s temperature rose by 3degrees, _______. 

A. great harm will be done to mankind         B.the sea level would go up by 10 centimeters

C. all the land in the world would be flooded     D.crops would be unable to grow on the earth

5. This passage mainly deals with ________.

A. the concept (概念) and the harm of the greenhouse  B. the relation betweengreenhouse gases and man

C. the concept and change of greenhouse effect            D.the effect of the rise of the earth’s temperature

试题答案

【答案】

BBDAC

【解析】略