It is 7 am and the alarm is going off. You know you have to be out of bed to catch the bus. But the urge to bury yourself in the bed is ever so strong. Sounds familiar? Why is it that teens find it difficult to get themselves out of bed in time every morning or stay sharp and focused during the first couple of hours of school?

During adolescence, the body goes through many changes and these include a shift in sleep patterns. Researchers from MIT have been tracking the body’s need for sleep in teenagers. They found that though adolescents need as much as 9.5 hours of sleep a day, they get to bed later and later with each passing year. In fact, the sleep cycle shifts later by as much as 12 to 18 minutes each year between the ages of 10 and 20! So by the time a 10­year­old who sleeps at 8 pm grows to be 17 or 18, his body naturally wants to stay up till 10：30 pm or 11 pm.

According to researchers, this is because of a hormone called melatonin (褪黑激素) that is secreted (分泌) by the pineal gland — a tiny structure deep inside the brain. Melatonin regulates the body’s natural day­night rhythms. It causes a person to become sleepy by lowering his body’s core temperature. In teens, melatonin is secreted much later in the evening and continues to increase throughout the night. This makes it difficult for teens to fall asleep earlier as they did in their younger years. Likewise, the effect of melatonin continues until much later in the morning, making it hard for them to wake up early.

A study found that at least one in four teens is tired and falls asleep in school at least once a week. During sleep, important body functions and brain activities happen. So how can teenagers get their sleep enough? The American Academy of Pediatrics (AAP) recommends that middle and high schools should start later — not before 8：30 am. This should give teens some more time to sleep at night.

21. From Paragraph 2, we can learn that if you sleep late, the next day you should ________.

A. stay sharp    B. skip breakfast   C. get up late    D. stay up late

22. What does the underlined word “this” in Paragraph 3 refer to?

A. The students want to stay up.                B. The shifts of the sleep cycle.

C. The pineal gland secretes melatonin.          D. The adolescents sleep late.

23. The teens go to sleep later than before because ________.

A. melatonin is secreted much later            B. melatonin regulates the sleep time

C. they sleep a lot in the daytime              D. they need to finish their homework

24. According to AAP’s recommendation, middle and high schools should ________.

A. let teens sleep in the day    B. let the students be active

C. delay the start time    D. start later at 8 am

 “Image is everything.”  If there is no fact behind the image, the product, service or person will fail at last.

First of all, one should consider how important image is in the selling of products and services. But if the product or service does not live up to the image that was created, the customer will be very dissatisfied and possibly ask for their money back. For example, the Arthur Andersen accounting firm had spent decades building up an image of trustworthiness. But the recent scandal (丑闻) showed that behind that image, it had dishonest business practices. Despite the previous positive image, the firm is being accused of criminal actions and it will probably not survive as a business unit. Although the image had been nearly perfect, the reality behind the image has led to the downfall of the world famous accounting firm.

Similarly, people especially politicians and movie stars try to ensure they are seen in all the right places which can build up a very positive image in the view of the general commons. But once again, history is filled with examples of both politicians and movie stars that fell from grace like the story of the Hollywood actor giving in to the pressures of fame and fortune. With people, just as with products and services, image is certainly important, but without positive substance(本质) behind the image, failure is close.

To summarize, it is clear that an appealing image is extremely important to success, whether that image is related to selling a product or service or to the " selling" of a person. But image is only half of the equation. What lies behind that image is every bit as important as the image itself—the person or product must deliver on that image or there is little chance for long-term success.

25. The downfall of the Arthur Andersen accounting firm is due to ______.

A. its dishonesty in business          B. its previous images 

 C. its bad management              D. its poor service

26. Why did some famous people fall from grace?

A. Their images were not well built up.          

  B. They failed to live up to their images.

C. They felt much pressure from the public.        

D. They paid little attention to fame and fortune.

27. The structure of the passage is             .

A.        B.     C.      D.

New rules will let millions of Americans know where most of their food comes from. The law is known as COOL -- Country of Origin Labeling(标签).

American congress first passed the law in 2002. Stores have had to label seafood by country of origin since 2005. But industry pressure delayed other requirements until last week.

Products that must now be labeled include fresh fruits and vegetables, muscle meats and some kinds of nuts. But the rules are complex, and many foods are not included. For example, organ meats are free to be labeled. So are processed foods, including cooked or smoked foods.

The same food may sometimes have to be labeled and other times not. Fresh or frozen peas, for example, have to be labeled but not canned peas. Foods that are mixed with other foods are also excluded. Mixed nuts, for example, do not need to be labeled. The same is true of a salad mix that contains different things like lettuce and carrots. Or a fruit cup that combines different fruits. Also, the law doesn’t include restaurants and other food service organizations. Department of Agriculture officials say the law is really meant for larger grocery stores.

The United States has imported more and more food in recent years to save money and expand choices. Country-of-origin labeling has become more common lately but has still been limited in many stores.

Food safety is one reason why some shoppers pay close attention to where foods came from. For example, when a large number of people recently got sick from salmonella(沙门菌病), officials blamed peppers from Mexico. Yet the last big food scare involved spinach grown in California. But labeling is also a way for people to know they are getting what they want. Some want to buy local foods or foods from a particular country.

The country-of-origin labeling law gives stores 30 days to correct any violations(违反) that are found. Stores and suppliers that are found to be deliberately violating the law could be fined 1,000 dollars per violation. Federal inspectors are not to take action to enforce(实施) the law for six months to give time for an education campaign.

Some food safety activists say they are generally pleased with the law. They call it a good step that will give people more useful information.

28. Why has more and more food been imported to the United States in recent years?

A. It is economical and provides people with more choices.

B. Foreign food is of higher quality than native food.

C. Americans need more and more food recently.

D. The United States is short of food supply.

29. Consumers are more concerned about where foods come from because________.

A. they are curious about the origin of the food.

B. most of them are particular about the tastes

C. they are concerned about food safety

D. most of them are food safety activists

30. The new rules of the country-of-origin labeling law will come into effect________.

A. right now          B. in a month       C. in three months       D. in half a year

31. Which of the following can be inferred from the text?

A. Store owners are most likely to be the supporters of the law.

B. The government of America will possibly forbid importing peppers from Mexico.

C. Federal inspectors couldn’ t take measures to enforce the law.

D. Most Americans prefer imported vegetables to the vegetables grown in local places.

 It is often said that man has become the enemy of our planet. This is no exaggeration(夸张), for reports show that man’s greed has done much to destroy the earth. Man, in his greedy desire for financial growth, has polluted the air, land and water, and has robbed our valuable natural resources. Man’s industrial plants pour out poisonous waste that pollutes the sea and puts life in the sea under the threat of dying out; at the same time, they release huge amounts of carbon dioxide, chlorofluorocarbons (CFCs) and other pollutants. Small wonder that the air now is much warmer and more impure(不纯净) than ever before.

Of course, this is not just because of man’s greed—it is man’s pressing need as well. For instance, in developing countries, huge financial foreign debts have forced governments to approve the cutting of forests for agriculture or ranching(牧场经营). As a result, forests are cut down just to meet man’s immediate needs.

Perhaps unknowingly, man has changed the make-up of the earth's atmosphere. Scientific studies have shown that CFCs used in refrigerators and industrial cleaners are fast destroying the ozone layer—a protective layer in the atmosphere that protects us against the harmful effects of the sun’s ultraviolet (紫外线) rays. In fact, documented reports have shown a terrible fact that there are “holes” in the ozone layer over the Antarctic. And they appear to be expanding.

Having these environmental problems, world leaders have shown deep concern. The UN Environmental Programme (UNEP) has arranged international agreements like the Vienna convention of 1985 and the Montreal Protocol of 1989 to preserve the ozone layer by controlling the production, use and trade of destructive chemicals.

There may be some doubt as to how effectual these agreements may be, given that some countries still maintain an “I-don’t-care” attitude. Their attitude is probably due to their failure to grasp the importance of the problem. Then, there is no doubt that environmental education on an international scale(规模) is greatly needed, so that all countries, great and small—the “haves” and the “have nots”—may realize their responsibilities for our planet.

In the meantime, the UNEP seems to have taken steps in the right direction, and it is hoped that in the not so distant future, all nations of the world will join hands in saving mother earth.

32. Which of the following is a reason for the cutting and burning of forests?

A. To build houses for more population.             B. To have land for agriculture.

C. To export trees to other countries.                 D. To build industrial plants. 

33. The holes in the ozone layer are largely due to________.

A. man’s research activities                         B. the greenhouse effect

C. the ultraviolent                                       D. harmful chemicals

34. Why don’t some countries care about the problem of the environment?

A. They don’t want to put their lives in danger.

B. They just don’t know how to solve the problem.

C. They haven’t realized the seriousness of the problem.

D. They don’t want to break their international commitment.

35. What is the author’s attitude towards the future of the environment?

A. Hopeful.           B. Unconcerned                   C. Doubtful                  D. Objective

If you feel depressed, it’s best to do something about it — depression doesn’t just go away on its own. In addition to getting help from a doctor or counselor, here are four things you can do to feel better.

Exercise. Take a 15－30 minutes walk every day — or dance, jog, or bike if you prefer. People who are depressed may not feel much like being active. ___36__ Once you get in the exercise habit, it won’t take long to notice a difference in your mood.

Cherish yourself with good nutrition. Depression can affect appetite. One person may not feel like eating at all, but another might overeat. If depression has affected your eating, you’ll need to be extra mindful of getting the right food. ___37___ So eat plenty of fruits and vegetables and get regular meals (even if you don’t feel hungry, try to eat something light, like a piece of fruit, to keep you going)．

Identify troubles. ___38___ When you know what’s got you feeling blue and why, talk about it with a caring friend. Talking is a way to release the feelings and to receive some understanding. If there’s no one to tell, pouring your heart out to a journal work just as well.

___39___ Depression affects a person’s thoughts, making everything seem dark, negative and hopeless. If depression has you noticing only the negative, make an effort to notice the good things in life. Try to notice one thing, and then try to think of one more. Consider your strengths, gifts, or blessings. Most of all, don’t forget to be patient with yourself. ___40___

A．Look on the bright side.

B．Take action to solve problems.

C．But make yourself do it anyway.

D．Depression takes time to heal.

E．Proper nutrition can influence a person’s mood and energy.

F．With depression, a person’s creativity and sense of fun may seem blocked.

G．Try to make out any situations that have contributed to your depression.