题目内容
听力原文： We can read of things that happened 5000 years ago in the Near East, where people first learned to write. But there are some parts of the word where even now people cannot write. The only way that they can preserve their history is to recount it as sagas—legends handed down from one generation to another. (29)These legends are useful because they can tell us something about migrations of people who lived long ago, but none could write down what they did.
(30) Anthropologists wondered where the remote ancestors of the Polynesian people now living in the Pacific Islands came from. The sagas of these people explain that some of them came from Indonesia about 2000 years ago.
But the first people who were like ourselves lived so long ago that even their sagas, if they had any, are forgotten. So archaeologists have neither history nor legends to help them to find out where the first 'modern men' came from.
(31) Fortunately, however, ancient men made tools of stone, especially flint, because this is easier to shape than other kinds. They may also have used wood and skins, but these have rotted away. (31)Stone does not decay, and so the tools of long ago have remained when even the bones of the men who made them have disappeared without trace.
(30)
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A．She'll get the things the man needs.B．Sally wants to go to the bookstore too.C．There
听力原文：W: (22) In Britain we are often told that people are leaving the big cities to live in the countryside but is this the case worldwide？
M: Not at all. (22)If you look at the biggest cities in 1950, seven out of the top ten were in the developed countries. However, by the year 2000, the developing countries will have eight out of the top ten. (22) (23)New York, which in 1950 was number one with a population of around 12 million, will only be the sixth largest city in the world with an extra of 2 million.
W: And London？
M: London, which was number two, won't even be in the top ten. Its population iii 1950 was about 10 million.
W: Why is this happening？ Why are people moving to the big cities from the country in developing countries？
M: Tile reasons are complex but many are moving to look for jobs. And the problems this creates are enormous. (24) Just imagine the kinds of difficulties this is going to cause in terms of health, transport and education.
W: Yes. What about tile cities of Asia？ Will they be experiencing a similar sort of growth？
M: In some cases, yes. Calcutta in India which was No. 10 in the league iii 1950 is expected to be the fourth biggest city in the world with a population of 16 million, four times in its size ill just 50 years.
W: What about Japan？
M: Ah! Well, Tokyo was number three in 1950; at the beginning of the next century, its population will increase by 18 million, three times of the year 1950. (25)Looking at the other major cities in Asia, Shanghai and Seoul will be in the top ten as well but, perhaps surprisingly, not Beijing or Hong Kong.
(26)
W: I'd be glad to show you around, but I'm very busy right now. could you come back at about 3:30？
Q: What will the man probably do？
(16)
Genetic Testing
Genetic testing is transforming medicine and the way families think about their health. As science uncovers the complicated secrets of DNA, we face difficult choices and new challenges. About Genetic Testing
The year was 1895 and Pauline Gross, a young actress, was scared. Gross knew nothing about the human-genome (基因组，染色体组) project--such medical triumphs, but she did know about a nasty disease called cancer, and it was running through her family. "I'm healthy now," she often told Dr. Aldred Warthin a pathologist at the University of Michigan, "but I fully expect to die an early death."
At the time, Gross's prediction was based solely on observation: family members had died of cancer; she would, too. Today, more than 100 years later, Gross's relatives have a much more clinical option: genetic testing. With a simple blood test, they can peer into their own DNA, learning--while still perfectly healthy--whether they carry an inheritable gene mutation (突变) that has dogged their family for decades and puts them at serious risk.
Take the Testing
Testing is just one piece of the genomic revolution. A major goal is to create new sophisticated therapies that home in on a disease's biological source, then fix the problem. Already, genes are helping to predict a patient's response to existing medications. A prime example, taken by Dr. Wylie Burke of the University of Washington, is a variant of a gene called TPMT, which can lead to life-threatening reactions to certain doses of chemotherapy (化学疗法). A genetic test can guide safe and appropriate treatment. Two genes have been identified that influence a person's response to some anti-blood-clotting drug. And scientists are uncovering genetic differences in the way people respond to other widely used medications, like antidepressants (搞抑郁药).
Knowing a patient's genotype, or genetic profile, may also help researchers uncover new preventive therapies for sticky diseases. At Johns Hopkins University School of Medicine, Dr. Christopher Ross has tested several compounds shown to slow the progression of Huntington's in mice. Now he wants to test them in people who are positive for the Huntington's mutation but have not developed symptoms--a novel approach to clinical drug trials, which almost always involve sick people seeking cures. "We're using genetics to move from treating the disease after it happens," he says, "to preventing the worst symptoms of the disease before it happens."
It's not just their own health that people care about. There is also the desire to get rid of disease from the family tree. Therefore, the future is what drives many adults to the clinic. The gene tests currently offered for certain diseases, like breast cancer, affect only a small percentage of total cases. Inherited mutations contribute to just 5 to 10 percent of all breast cancers. But the impact on a single life can be huge. The key: being able to do something to ward off disease. "Genetic testing offers us profound insight," says Dr. Stephen Gruber, of the University of Michigan. "But it has to be balanced with our ability to care for these patients."
Genetic testing today starts at the earliest stages of life. Couples planning to have children can be screened prior to conception to see if they are carriers of genetic diseases; prenatal (产前) tests are offered during pregnancy, and states now screen newborns for as many as 29 conditions, the majority of them genetic disorders. For Jana and Tom Monaco, of Woodbridge, Va. , early testing has made an enormous difference in the lives of their children. Their journey began in 2001, when their seemingly healthy third child, 3-year-old Stephen, developed a life-threatening stomach virus that led to severe brain damage. His diagnosis: a rare but treatable disease called isovaleric acidemia (IVA). Unknowingly, Jana and her husband were carriers
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