A green house is a building made of glass which is used for keeping plants warm when the outside temperature is low. In a similar way there are several gases in the atmosphere 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 trap heat in the atmosphere is called the “greenhouse effect”. This is not simply air pollution. Most of the main greenhouse gases exist naturally in small amounts in our atmosphere, and without them the earth would be 30 degrees colder and human life wound not exist. In other words, the greenhouse effect is a natural course which is to some degree helpful to us.

The problem is that in the last century and a half, we have been putting too many of these gases into the earth’s atmosphere by burning large quantities of coal and oil and by cutting down forests. The rapid increase in greenhouse gases is making the world warmer. The world’s temperature has already gone up by half a degree this century, and the sea level has risen by 10 centimetres. If the amount of carbon dioxide in the atmosphere doubles there will probably be a rise in the earth’s temperature of between 1and 4. 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 and unable to produce crops. It is important, too, to consider that there may be a delay of about 30 years in the greenhouse effect. This means that we are probably experiencing only now the effect of the gases put into the atmosphere before the 1960s. Since then, these gases have greatly increased.

1. “ Greenhouse effect” means ___________.

A. The way in which gases are used for keeping plants warm

B. a natural course which is to some degree helpful to us

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

D. the whole course in which greenhouse gases prevent heat

2. If there were no greenhouse effect, ________

A. no plants would grow on our planer

B. the earth would be thirty degrees colder

C. man could not live on the earth

D. all of the above answers are correct

3. Which of the following is NOT true?

A. Burning too much coal and oil produces lots of greenhouse gases.

B. It has become warmer on the earth now than in the past.

C. gases put into the atmosphere now will effect the earth years later.

D. the temperature in a greenhouse is as that in the atmosphere.

4. Suppose the earth’s temperature rose by 3 degrees_________.

A. great harm would be done to mankind

B. the sea level would go up by 10 centimetres

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 and harm of greenhouse effect

B. the relation between greenhouse gases and man

C. the concept and change of greenhouse effect

D. the effect of the rise of the earth’s temperature

Do you find getting up in the morning so difficult that it is painful?This might be called laziness,but Dr.Klaitman has a new explanation.He has proved that everyone has a daily energy cycle.

During the hours when you labor through your work,you may say that you're “hot”.That's true.The time of the day when you feel most energetic is when your cycle of body temperature is at its peak.For some people the peak comes during the forenoon.For others it comes in the afternoon or evening.No one has discovered why this is so,but it leads to such familliar monologues(独白)as:“Get up,John!You will be late for work again!”The possible explanation to the trouble is that John is at his temperature and energy peak in the evening.Much family quarrelling ends when husbands and wives realized what these energy cycles mean,and which cycle each member of the family has.

You can't change your energy cycle,but you can learn to make your life fit it better.Habit can help,Dr.Klaitman believes.Maybe you're sleepy in the evening but feel you must stay up late anyway.Counteract(阻碍)your cycle to some extent by habitually staying up later than you want to.If your energy is low in the morning but you have an important job to do early in the day, rise before your usual hour.This won't change your cycle,but you’ll get up steam and work better at your low point.

1.If a person finds getting up early difficult,a problem most probably is­­­­­­­______.

A.he is a lazy person

B.he refuses to follow his own energy cycle

C.he is not sure when his energy is low

D.he is at his peak in the afternoon or evening

2.Which of the following may lead to family quarrels according to the passage?

A.Unawareness of energy cycles.

B.Familiar monologues.

C.A change in a family member's energy cycle.

D.Attempts to control the energy cycle of other family members.

3.If one wants to work more efficiently at his low point in the morning,he should_______.

A.change his energy cycle B.overcome his laziness

C.get up earlier than usual D.go to bed earlier

What should you think about in trying to find your career? You are probably better at some school subjects than others. These may show strengths that you can use in your work. A boy who is good at mathematics can use that in an engineering career. A girl who spells well and likes English may be good at office work. So it is important to know the subjects you do well in at school. On the other hand, you may not have any specially strong or weak subjects but your records show a general satisfactory standard. Although not all subjects can be used directly in a job, they may have indirect value. A knowledge of history is not required for most jobs but if history is one of your good subjects you will have learned to remember facts and details. This is an ability that can be useful in many jobs.

Your school may have taught you skills, such as typing or technical drawing, which you can use in your work. You may be good at metal work or cookery and look for a job where you can improve these skills.

If you have had a part-time job on Saturdays or in the summer, think what you gained from it. If nothing else, you may have learned how to get to work on time, to follow instruction and to get on with older workers. You may have learned to give correct change in a shop, for example. Just as important, you may become interested in a particular industry or career you see from the inside in a part-time job.

Facing your weak points is also part of knowing yourself. You may be all thumbs when you handle tools, perhaps you are a poor speller or cannot add up a column of figures. It is bitter to face your weaknesses than to pretend they do not exist. Your school record, for instance, may not be too good, yet it is an important part of your background. You should not be apologetic about it but instead recognize that you will have a chance of a fresh start at work.

1. Which of the following best sums up the first paragraph?

A. The importance of doing well at school.

B. Using school performance to help to choose a career.

C. The importance of being good at all subjects.

D. The indirect value of school work.

2. The writer thinks that for a student to have a part-time job is probably _________.

A. a waste of time that could have been spent on study

B. useful for his future work

C. a good way to earn extra money

D. a good way to find out his weak points

3. According to the passage, if a student’s school record is not