题目内容

Ears are for hearing — everyone knows that. But for a creature called the Cuvier’s beaked whale, hearing starts in the throat (喉咙), a new study found.
The observation might help explain how all whales hear. The work might also help scientists understand how animals are affected by underwater sonar (声呐). This sonar, used by some ships, sends out sound waves to locate underwater objects.
The Cuvier’s beaked whale is a so-called toothed whale. Toothed whales dive deep into the ocean in search of food. As the whales hunt, they produce sounds that reach objects and then return to the whales. This allows the animals to “see” the shape, size, and location of objects, even when they’re 1,000 meters under the sea, where it is totally dark.
To better understand how the whale hears, researchers from San Diego State University in California took X rays of two Cuvier’s beaked whales. The whales had died and washed up on the beach.
Ted Cranford and his colleagues used the images to make a computer model of a Cuvier’s beaked whale’s head. Then, they modeled the process of sound traveling through the head.
The researchers knew that some sounds get to the ears of a toothed whale through a structure (构造) called “the window for sound”. Found on the lower jaw, this structure is very thin on the outside and has a large pad (垫) of fat on the inside.
When the researchers used their computer model to work out how sound waves travel in the whale’s head, they were surprised to find that sounds coming from right in front of the whale actually travel under the animal’s jaw. From there, sound waves move through the throat, into a hole in the back of the jaw, and finally to the pad of fat near the animal’s ears.
69. 小题1:Toothed whales look for food under the sea by ______.
A．watching the shape and size of their objectsB．diving deep into the sea
C．sending and receiving soundsD．making lots of noises
70. 小题2:Researchers took X rays of two Cuvier’s beaked whales in order to ______.
A．find out why they had died and washed up on the beach
B．make a computer model of a Cuvier’s beaked whale’s head
C．make sure that sound travels through the head
D．know more about the way the whale hears
71. 小题3: Which of the following describes the way taken by sound waves through a Cuvier’s beaked whale?
A．A hole in the back of the jaw → the ears → the jaw → the throat.
B． The jaw → the throat → a hole in the back of the jaw → the ears.
C． The throat → the jaw → the ears → a hole in the back of the jaw.
D．The ears → the throat → a hole in the back of the jaw → the jaw.
72. 小题4:Which of the following is TRUE according to this passage?
A．The throat is important to the Cuvier’s beaked whale’s hearing.
B．Ships send out sound waves like a Cuvier’s beaked whale.
C．The ears are actually useless to the Cuvier’s beaked whale.
D．The researchers haven’t found how the whales hear.

小题1:C
小题2:D
小题3:B
小题4:A
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A serious problem for today’s society is who should be responsible for our elderly(老年人) and how to improve their lives. It is not only a financial problem but also a question of the system we want for our society. I would like to suggest several possible solutions to this problem.
First, employers should take the responsibility for their retired employees. To make this possible, a percentage of profits should be set aside for this purpose. But when a company must take life-long responsibility for its employees, it may suffer from a commercial disadvantage due to higher employee costs.
Another way of solving the problem is to return the responsibility to the individual. This means each person must save during his working years to pay for his years of retirement. This does not seem a very fair model since some people have enough trouble paying for their daily life without trying to earn extra to cover their retirement years. This means the government might have to step in to care for the poor.
In addition, the government could take responsibility for the care of the elderly. This could be financed through government taxes to increase the level of pensions（养老金）. Furthermore, some in-situation should be created for senior citizens, which can help provide a comfortable life for them. Unfortunately, as the present situation in our country shows, this is not a truly viable answer. The government can seldom afford to care for the elderly, particularly when it is busy trying to care for the young.
One further solution is that the government or social organizations establish some working places especially for the elderly where they are independent.
To sum up, all these options（选择）have advantages and disadvantages. Therefore, it is reasonable to expect that some combination of these options may be needed to provide the care we hope to give to our elderly generations.
小题1:What is the passage mainly about?
A．The problems faced by the old in society.
B．Why we should take responsibility for the old.
C．How we can improve the lives of the old.
D．Where the old can go to get their pensions.
小题2:According to the passage, how can the government help to improve the lives of retired people?
A．Set aside some profits to help people with problems after they retire.
B．Increase savings levels of people during their working years.
C．Increase the discounts for food and transport for the old.
D．Make available pensions for those who have retired.
小题3:The underlined word “viable” most probably means “__________”.
A．impossibleB．practicalC．usefulD．successful
小题4:What can be concluded from the passage?
A．Taking care of the old is mainly an issue of money.
B．Employers should allow their workers to retire at a later age.
C．Becoming independent should be the goal of most old people.
D．There is no single solution to the problems of the old.
小题5:What is the writer’s main purpose in writing this article?
A．To point out the need for government support for old people.
B．To make general readers aware of the problems of retired people.
C．To discuss some possible solutions to an important social problem.
D．To instruct retired people on how they can have a happier life.

The sleep debt is the difference between the amount of sleep you should get and the amount you actually get. It grows every time we skim some extra minutes off our nightly sleep. “People accumulate sleep debts gradually,” says Dr. William Dement, founder of the Stanford University Sleep Clinic. Studies show that such short-term lack of sleep leads to a foggy brain, impaired vision, worsened driving and troubled remembering. Long- term effects include obesity, insulin(胰岛素) resistance, and heart disease.
A 2007 survey by the National Sleep Foundation reports that Americans sleep for 6.9 hours per night, 6.8 hours on average during the week and 7.4 hours on the weekends. Generally, experts recommend eight hours of sleep per night, although some people may require only six hours of sleep while others need ten. That means on average, Americans lose one hour of sleep each night more than two full weeks of sleep every year.
The good news is that the sleep debt can be repaid with some work, though it won’t happen when you sleep longer for once. Adding an extra hour or two hours of sleep a night is the way to catch up. For the long-term sleep shortage, it takes a few months to get back to natural sleeping pattern, says Lawrence J. Epstein, medical director of the Harvard Sleep Health Center.
Go to bed when you are tired, allowing your body to wake you in the morning, with no alarm clock. You may find yourself uncomfortable at the beginning of the recovery cycle. Expect to bank to ten hours shut-eye per night. As the days pass, however, the amount of sleeping time will gradually decrease. For recovery sleep, both the hours of the sleep and the intensity(强度) of the sleep are important. The most refreshing sleep occurs during deep sleep, which is generally considered a restorative (促使健康的) period for the brain. And when you sleep for more hours, you allow your brain to spend more time relaxing.
As you reduce the sleep debt, your body will come to rest at a sleeping pattern that is specifically right for you. Sleep researcher believe that genes determine our individual sleeping patterns. So you can’t train yourself to be a “short sleeper”. A 2005 study in the journal Sleep found that the more tired we get, the less tired we feel.
46. Which of the following is NOT the side effect of sleep debt?
A. Putting on weight.  B. Having a bad memory. 
C. Having trouble eating food.  D. A temporary loss of eyesight.
47. We learn from the 2007 survey that _______.
A. Americans generally don’t have enough sleep
B. Americans sleep too much over the weekends
C. everyone is supposed to sleep for eight hours
D. most people lack two weeks of sleep every year
48. What should we do to make up for the sleep shortage?
A. We should go to sleep when we are free.
B. We should sleep for at least ten hours every day.
C. We should sleep for one or two more hours at night.
D. We should sleep day and night during the holidays.
49. Why is the intensity of the sleep important to us?
A. Our brain is resting when we are sleeping deeply.
B. Deep sleep helps our brain to fully recover.
C. We feel more relaxed when sleeping soundly.
D. Short sleep makes our body more refreshing.
50. The author seems to believe that _________.
A. the more tired we are getting, the more sleep we need 
B. the sleeping patterns have nothing to do with our genes
C. it is possible for us to reduce our sleep time by training
D. it is wise for us to adapt to our natural sleeping patterns.

Scientists have developed a water treatment system that they say is a powerful but simple way to save lives. Four grams of chemicals can treat ten liters of dirty water for a low cost, about ten cents.
Experts say infections from dirty water kill several thousand children in developing countries every day. The Procter and Gamble company has been developing the "PUR Purifier of Water" system since 1995. The company has been working with the United States Centers for Disease control and Prevention(C.D.C.).
C.D.C. researchers tested it in Guatemala, Pakistan and Kenya. Procter and Gamble researcher Greg Allgood says cases of diarrhea(腹泻) in those studies fell by about 50 percent. Researchers from Johns Hopkins University in Maryland tested the system at a refugee camp in Liberia. Mr. Allgood says that study found a reduction of more than 90 percent. Use of the system is being expanded worldwide.
The treatment contains bleach(漂白剂) to kill disease-causing organisms. It also contains something that dirt and other particles stick to. Mr. Allgood says the chemicals can remove lead and other dangerous metals and even agricultural poisons like D.D.T.
Mr. Allgood heads the Children's Safe Drinking Water program at Procter and Gamble. He says about forty million packets of the treatment have been given to countries for free. They have been used in emergencies and in areas with limited supplies of clean water.
Clean water is a limited resource in many parts of the world. Delegates from about 130 nations attended the Fourth World Water Forum last month in Mexico City. Scientists, policy experts and others discussed ways to provide clean water to the world’s poor. Organizers say more than twenty percent of the world population lacks clean drinking water. The final declaration did not go so far as to declare water a human right. But it did say that governments, not private companies, must take the lead in improving the public’s ability to have clean water.
46. What is mainly talked about in this passage?
A. Water pollution around the world.
B. The causes of diarrhea in African countries.
C. A newly developed water treatment system.
D. The Fourth World Water Forum in Mexico City.
47. Which of the following developed the water treatment system?
A. The US Centers for Disease Control and Prevention.
B. The Procter and Gamble Company and C.D.C.
C. The Children’s Safe Drinking Water Program.
D. Johns Hopkins University.
48. Which of the following about the new water treatment system is NOT true?
A. It is effective but very expensive.
B. It was tested in Guatemala, Pakistan and Kenya.
C. It is being expanded worldwide.
D. It can remove dangerous metals in the water.
49. Which of the following shows that the shortage of clean water is a serious problem?
A. Forty million packets of the treatment have been given to countries for free.
B. Delegates from about 130 nations attended the Fourth World Water Forum.
C. Four grams of chemicals can treat liters of dirty water for a low cost.
D. Infections from dirty water kill several thousand children every day.
50. The best title for this article is ______.
A. A Small Packet of Chemicals, a Big Effect on Dirty Water
B. The Procter and Gamble Company and C.D.C.
C. The Shortage of Clean Water                           
D. How to Cure Diarrhea
The rising costs of health care have become a problem for man y countries in the world. To deal with this problem, it is recommended that a big part of the state health budget be used for health education and disease prevention instead of treatment. Actually, many kinds of diseases are preventable in many ways and preventing a disease is usually much cheaper than treating it. For example, people could avoid catching a cold if they dressed warmly when the weather starts getting cold. But many people get sick because they fail to do so, and have to spend money seeing a doctor.
Daily habits like eating more healthy food would have kept millions of families from becoming bankruptif the patients had taken ways for early prevention. For example, keeping a balanced diet, such as not consuming too much animal fat and trying to have enough vegetables and fruits, seems to be quite important.
　　One very effective and costless way of prevention is regular exercise, which is necessary for a healthy mind and body. Regular exercise, such as running, walking, and playing sports is a good way to make people feel better or reduce stress.
In addition, health education plays a key role in improving people’s health. By giving people more information about health, countries could help people understand the importance of disease prevention and ways to achieve it. For example, knowing one’s family medical history is an effective way to help keep healthy. Information about health problems among close relatives will make them aware of what they should do to prevent certain diseases through lifestyle changes, which will work before it is too late.    
However, paying more attention to disease prevention does not mean medical treatment is unimportant. After all, prevention and treatment are just two different means toward the same effect. In conclusion, we could save money on health care and treat patients more successfully if our country spends more money on health prevention and education.
小题1:What’s the best title of the passage?
A．Prevention or Education?B．Exercise or Illness?
C．Health or Illness?D．Prevention or Treatment?
小题2:Which of the following can replace the underlined word “bankrupt”?
A．Unable to be cured.B．Unable to pay one’s debts.
C．Stronger than ever before.D．More successful than ever before.
小题3:We learn from the passage that ______．
A．dressing warmly can prevent diseases.
B．a balanced diet is cheaper than regular exercise.
C．the more health education, the better.
D．the government’s health budget should be increased.
小题4:Which of the following shows the structure of the passage?
Even facts “forgotten” by people during a busy day may be retrieved if this is followed by a good night’s sleep.
Researchers from the University of Chicago asked volunteers to remember simple words．Many found their memories letting them down towards the end of the day, but the following morning, those who had slept well could recall much more.
Researchers, writing in the journal Nature, said the brain could “rescue” lost memories during the night.
When the brain is first asked to remember something that memory is laid down in an “unstable” state, meaning that it is possible that it could be lost．At some point, the brain consolidates those it deems important into a “stable”, more permanent state．However, the Chicago researchers suggested that it was possible for a “stable” memory to be made “unstable” again．This would mean that memories could be modified then filed away again in the face of new experiences.
The 12 volunteers tested in the experiment were played words created through a speech synthesizer which were purposely difficult to understand．Initially, the written version of the word  from the audio version only．Tests revealed that the ability to recall the right word tended to tail off as the day ended.
However, when the volunteers were retested after a good night’s sleep, they were able to recall some words that they had “ forgotten” the previous evening.
Dr Daniel, one of the study authors, said: “Sleep consolidates memories, protecting them against subsequent interference or decay．Sleep also appears to “recover” or restore memories.” He said: “If performance is reduced by decay, sleep might actively recover what has been lost.”
Dr Karim Nader, from the Department of Psychology in McGill University in Montreal, said: “Memory research is undergoing a transformation---no longer is memory thought to be a hard-writing of the brain, instead it seems to be a process of storage and restorage.”
Sleep helps some memories “mature” and also prunes out unimportant memories.
小题1:What does the first paragraph implies?
A．A busy day makes people forget things easily.
B．People need a good night’s sleep after a busy day.
C．A good night’s sleep helps memories.
D．A good night’s sleep helps people forget a busy day.
小题2:The words the 12 volunteers played in the experiment were not ____
A．created through a speech synthesizer
B．hard to understand
C．available at the beginning
D．designed to test people’s ability of understanding
小题3:According to the passage, memory_____
A．is a hard-writing of the brain
B．is not a process of storage
C．is not a process of restorage
D．will be mature with the help of sleep
小题4:Which of the following is NOT true?
A．When people first remember something, the memory is in an “unstable state”.
B．The brain will change those important unstable memories into stable.
C．Once the memory become stable, it will never become unstable again.
D．Sleep can protect memories from being harmed.
With winter fast approaching, flu season is here. People can easily catch the flu bug and they try to fight it with western medicine, traditional Chinese medicine or some homemade secret recipes. Yet some of these strategies are ineffective or even harmful, the best way to counter the flu is to protect us from contracting（感染）it. So here are some good habits to protect people from contracting flu from the very beginning.
●During the day, keep the bedroom window open to let fresh air in．
●Wash your face with cold water in the morning and wash your feet with hot water in the evening. This practice can help boost blood circulation and improve the body's resistance.
●Do some exercises in the morning. such as jogging or shadowboxing（太极拳)for 10 minutes.
●Rinse(漱) your mouth with salt water or tea every morning and every evening. This can help kill flu bacteria, clear phlegm(痰）and keep the mouth fresh.
●Wear more clothes when it's cold and take some off when it's warm
●Get a bottle of vinegar or Chinese white wine at hand and smell it now and then. Their pungent smell can help people get refreshed and improve their body's resistance.
● Drink two kinds of beverages（饮料）before going to bed, which can help people stay away from the flu: soup made of radish（萝卜）and vinegar, and tea made of fresh ginger（生姜）．
●Close the doors and windows and put a pot of boiling vinegar in the room Vinegar steam is a good way to kill flu bacteria in the air.
小题1: Some people like washing their face with cold water in the morning and washing their feet with hot water in the evening perhaps because______．
A．they want to make themselves handsome or pretty
B．they know it is the best way to kill flu bacteria
C．they think it can strengthen blood circulation and improve their resistance
D．they have developed the good habit of living
小题2:According to the passage, we can know that the best way to fight the flu is to ______.
A．take western medicine or traditional Chinese medicine
B．avoid getting it at the very beginning
C．use some homemade secret recipes
D．drink two kinds of beverages before going to bed in winter
小题3: What would be the best title for this passage?
A．Eight habits to keep the flu awayB．The cause of contracting the flu
C．Winter and fluD．How to cure the flu
A new study has found no evidence that sunscreen, commonly used to reduce the risk of skin cancer, actually increases the risk.
Researchers from the University of Iowa based their findings on a review of 18 earlier studies that looked at the association between sunscreen use and melanoma (黑素瘤)．They said that they found faults in studies that had reported associations between sunscreen use and higher risk of melanoma.
Most health experts believe that by protecting the skin from the harmful effects of the sun, sunscreen helps prevent skin cancer, which is increasing in incidence (发生率) faster than any other cancer in the United States.
But questions has been raised about sunscreen and whether it may has opposite effect, perhaps by allowing people to remain exposed to the sun longer without burning.
The researchers said that among the problems with some earlier studies is that they often failed to take into account that those people most at risk for skin cancer--- people with fair skin and freckles (雀斑), for example--- are more likely to use sunscreen．As a result, it may appear that sunscreen users get cancer more often.
The studies, which generally relied on volunteers to recall their sunscreen use, were also unable to prove how well the products had been applied, said the new study.
小题1:People with fair skin and freckles         .
A．seldom use sunscreen
B．are more in danger of skin cancer
C．can be free from the harm of the sun
D．often expose themselves to the sun
小题2:We can learn from the passage that         .
A．sunscreen users get skin cancer more often
B．the volunteers have proved the effect of sunscreen
C．the new study was based on the experiences of volunteers
D．the number of skin cancer patients is increasing in America
小题3:Which of the following can be the best title for this passage?
A．Sunscreen to Prevent Skin Cancer
B．Sunscreen to Increase Skin Cancer
C．Skin Cancer Caused by Sunscreen
D．Skin Cancer Caused by Freckles
Dieters are often advised to stop drinking alcohol to avoid the extra calories lurking in a glass of wine or a favorite cocktail. But new research suggests that women who regularly consume moderate(适度的) amounts of alcohol are less likely to gain weight than nondrinkers and are at lower risk for obesity (fatness).
The findings, reported this week in the Archives of Internal Medicine, are based on a study of 19,220 United States women aged 30 to 40 who fall into the “normal weight” based on their body mass index. Researchers at Brigham and Women’s Hospital in Boston tracked the women’s drinking habits over 13 years. About 60 percent of the women were light or regular drinkers, while about 40 percent reported drinking no alcohol.
Over the course of the study, 41 percent of the women became overweight. Although alcohol is packed with calories, the nondrinkers in the study actually gained more weight over time: nine pounds, on average, compared with an average gain of about three pounds among regular moderate drinkers. The risk of becoming overweight was almost 30 percent lower for women who consumed one or two alcohol drinks a day, compared with nondrinkers.
The findings are certain to be confusing for women who continue to receive conflicting messages about the health benefits and risks of alcohol. Although moderate drinking is associated with better heart health, regular drinking also increases breast cancer risk.
The trend toward less weight gain among drinkers doesn’t appear to hold true for men. A 2003 study of British men showed that regular drinkers gained more weight than nondrinkers. Studies suggest that drinking alcohol has different effects on eating habits among men and women. Men typically add alcohol to their daily caloric intake, whereas women are more likely to substitute（替代）alcohol for food. In addition, there may be differences in how men and women metabolize（代谢）alcohol. Metabolic studies show that after men drink alcohol, they experience little if any metabolic change. But alcohol appears to slightly speed up a woman’s metabolism.
The findings don’t mean women should rush to drink alcohol to lose weight. Other research shows that once a person is already overweight, her alcohol metabolism is more efficient, and so an overweight woman may gain more weight from alcohol than a lean(瘦的) woman. The data do, however, suggest that for many women facing weight problems, the extra calories are probably not coming from alcoholic drinks.
小题1: According to the study, which of the following regular drinker is less likely to gain weight than nondrinkers?
             
A                 B                 C                  D
小题2:That men regular drinkers gained more weight than women regular drinkers is due to the following except ______.
A．women are more likely to substitute alcohol for food.
B．men drink alcohol much faster than women.
C．men and women metabolize alcohol differently.
D．men have different effects on eating habits with women.
小题3: The underlined word “whereas” may probably mean _______.
A．soB．in order thatC．butD．and then
小题4:What can a dieter probably do before reading this passage?
A．Rush to drink alcohol to lose weight
B．Add alcohol to his or her daily caloric intake.
C．Face the weight problems alone.
D．Try to stop drinking any alcohol or wine.

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