单选题Joe came to the window as the crowd chanted “Joe,Joe,Joe”　　A. repeated　　B. jumped　　C. maintained　　D. approached

单选题He is (certain) that the dictionary is just what 1 want．

单选题下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。 Robots May Allow Surgery in Space Small robots designed by University of Nebraska researchers may allow doctors on Earth to help perform surgery on patients in space. The tiny, wheeled robots, {{U}}(51) {{/U}} are about 3 inches tall and as wide as a lipstick case, can be slipped into small incisions (切口) and computer-controlled by surgeons in different locations. Some robots are equipped {{U}}(52) {{/U}} cameras and lights and can send images back to surgeons and others have surgical tools attached that can be {{U}} (53) {{/U}} remotely. "We think this is going to {{U}}(54) {{/U}} open surgery," Dr. Dmitry Oleynikov said at a news conference. Oleynikov is a {{U}}(55) {{/U}} in computer-assisted surgery at the Universities of Nebraska Medical Center in Omaha. Officials hope that NASA will teach {{U}}(56) {{/U}} to use the robots soon enough so that surgeries could one day be performed in space. On earth, the surgeons could control the robots themselves {{U}}(57) {{/U}} other locations. For example, the robots could enable surgeons in other places to {{U}}(58) {{/U}} on injured soldiers on the front line. Researchers plan to seek federal regulatory {{U}}(59) {{/U}} early next year. Tests on animals have been successful, and tests on humans in England will begin very soon. The camera-carrying robots can provide {{U}}(60) {{/U}} of affected areas and the ones with surgical tools will be able to maneuver (操控) inside the body in ways surgeons' hands can't. The views from the camera-carrying robots are {{U}}(61) {{/U}} than the naked eye, because they {{U}}(62) {{/U}} back color images that are magnified(放大). Because several robots can be inserted through one incision, they could reduce the amount and {{U}}(63) {{/U}} of cuts needed for surgery, which would decrease recovery time. This is particularly {{U}}(64) {{/U}} to those patients who have been debilitated (使虚弱) by long illness. Eventually, Oleynikov said, the tiny robots may enable surgeons to work without ever {{U}}(65) {{/U}} their hands in patients' bodies. "That's the goal ," Oleynikov said. "It's getting easier and easier. We can do even more with these devices. "

单选题Hair Detectives Scientists have found a way to use hair to figure out where a person is from and where that person has been. The finding could help solve crimes, among other useful applications. Water is central to the new technique. Our bodies break water down into its parts: hydrogen and oxygen. Atoms of these two elements end up in our tissues and hair. But not all water is the same. Hydrogen and oxygen atoms can vary in how much they weigh. Different forms of a single element are called isotopes. And depending on where you live, tap water contains unique proportions of the heavier and lighter isotopes of hydrogen and oxygen. Might hair record these watery quirks? That's what James R. Ehleringer, an environmental scientist at the University of Utah in Salt Lake City, wondered to find out he and his colleagues collected hair from barbers and hair stylists in 65 cities in 18 states across the United States. The researchers assumed that the hair they collected came from people who lived in the area. Even though people drink a lot of bottled water these days, the scientists found that hair overwhelmingly reflected the concentrations of hydrogen and oxygen isotopes in local tap water. That's probably because people usually cook their food in the local water. What's more, most of the other liquids people drink including milk and soft drinks contain large amounts of water that also come from sources within their region. Scientists already knew how the composition of water varies throughout the country. Ehlernger and colleagues combined that information with their results to predict the composition of hair in people from different regions. One hair sample used in Ehleringer's study came from a man who had recently moved from Beijing, China, to Salt Lake City. As his hair grew, it reflected his change in location. The new technique can't point to exactly where a person is from, because similar types of water appear in different regions that span a broad area but authorities can now use the information to analyze hair samples from criminals or crime victims and narrow their search for clues.

单选题{{B}}第三篇{{/B}} {{B}}Hair Detectives{{/B}} Scientists have found a way to use hair to figure out where a person is from and where that person has been. The finding could help solve crimes, among other useful applications. Water is central to the new technique. Our bodies break water down into its parts: hydrogen and oxygen. Atoms of these two elements end up in our tissues and hair. But not all water is the same. Hydrogen and oxygen atoms can vary in how much they weigh. Different forms of a single element are called isotopes. And depending on where you live, tap water contains unique proportions of the heavier and lighter isotopes of hydrogen and oxygen. Might hair record these watery quirks? That's what James R. Ehleringer, an environmental scientist at the University of Utah in Salt Lake City, wondered. To find out, he and his colleagues collected hair from barbers and hair stylists in 65 cities in 18 states across the United States. The researchers assumed that the hair they collected came from people who lived in the area. Even though people drink a lot of bottled water these days, the scientists found that hair overwhelmingly reflected the concentrations of hydrogen and oxygen isotopes in local tap water. That's probably because people usually cook their food in the local water. What's more, most of the other liquids people drink including milk and soft drinks contain large amounts of water that also come from sources within their region. Scientists already knew how the composition of water varies throughout the country. Ehleringer and colleagues combined that information with their results to predict the composition of hair in people from different regions. One hair sample used in Ehleringer's study came from a man who had recently moved from Beijing, China, to Salt Lake City, As his hair grew, it reflected his change in location. The new technique can't point to exactly where a person is from, because similar types of water appear in different regions that span a broad area. But authorities can now use the information to analyze hair samples from criminals or crime victims and narrow their search for clues.

单选题At the meeting both sides exchanged their views on a wide scope of topics they were interested in.

单选题Chinese people tend to use plants to remedy disease.A. diagnoseB. cureC. evaporateD. revise

单选题Rise in Number of Cancer Survivors Cancer is the second leading cause of death in the United States, after heart disease. In the 1 , it was often considered a death sentence. But many patients now live longer 2 of improvements in discovery and treatment. Researchers say death 3 in the United States from all cancers combined have fallen for thirty years. Survival rates have increased for most of the top fifteen cancers in both men and women, and for cancers in 4 . The National Cancer Institute and the Centers for Disease Control and Prevention studied the number of cancer survivors. A cancer survivor is defined 5 anyone who has been found to have cancer. This would include current patients. The study covered the period 6 1971 to 2001. The researchers found there are three 7 as many cancer survivors today as there were thirty years ago. In 1971, the United States had about three-million cancer 8 . Today there are about ten-million. The study also found that 64% of adults with cancer can expect to still be 9 in five years. Thirty years ago, the five-year survival rate was 50%. The government wants to 10 the five-year survival rate to 70% by 2010. The risk of cancer increases with age. The report says the majority of survivors are 65 years and 11 . But it says medical improvements have also helped children with cancer live 12 longer. Researchers say 80% of children with cancer will survive at least five years after the discovery. About 75% will survive at 13 ten years. In the 1970s, the five-year survival rate for children was about 50%. In the 1960s, most children did not survive cancer. Researchers say they 14 more improvements in cancer treatment in the future. In fact, they say traditional cancer-prevention programs are not enough anymore. They say public health programs should also aim to support the 15 numbers of cancer survivors and their families.

单选题Today, conventional financial controls are still exercised in some minor areas such as billing and vocational training.

单选题Accompanied by cheerful music, we began to dance.

单选题As the industry developing in these years, most of the rivers have been contaminated by sewage (污水).

单选题下面有3篇短文，每篇短文后有5道题。请根据短文内容，为每题确定1个最佳选项。{{B}}第一篇{{/B}} Arctic Melt Earth's North and South Poles are famous for being cold and icy．Last year，however，the amount of ice in the Arctic Ocean(北冰洋)fell to a record low． Normally，ice builds in Arctic waters around the North Pole each winter and shrinks(缩小)during the summer．But for many years，the amount of ice left by the end of summer has been declining． Since 1979，each decade has seen an 11.4 percent drop in end-of-summer ice cover．Between 1981 and 2000．ice in the Arctic lost 22 percent of its thickness-becoming 1.13 meters thinner． Last summer，Arctic sea ice reached its thinnest levels yet．By the end of summer 2007，the ice had shrunk to cover just 4.2 million square kilometers．That's 38 percent less area than the average cover at that time of year．And it's a very large 23 percent below the previous record low，which was set just 2 years ago．This continuing trend has made scientists concerned． There may be several reasons for the ice melt，says Jinlun Zhang，an oceanographer(海洋学家)at the University of Washington in Seattle．Unusually strong winds blew through the Arctic last summer． The winds pushed much of the ice out of the central Arctic．1eaving a large area of thin ice and open wa ter． Scientists also suspect that fewer clouds cover the Arctic now than in the past．Clearer skies allow more sunlight to reach the ocean．The extra heat warms both the water and the atmosphere．In parts of the Arctic Ocean last year，surface temperatures were 3.5? Celsius warmer than average and 1.5℃ warmer than the previous record high． With both air and water getting warmer，the ice is melting from both above and below．In some parts of the Beaufort Sea，north of Alaska and western Canada，ice that measured 3.3 meters thick at the beginning of the summer measured just 50 cm by season's end． The new measurements suggest that melting is far more severe than scientists have seen by just looking at ice cover from above．Some scientists fear that the Arctic is stuck in a warming trend from which it may never recover．

单选题{{B}}第三篇{{/B}} Live with Computer After too long on the net, even a phone call can be a shock. My boyfriend's Liverpudlian (利物浦的) accent suddenly becomes indecipherable (难懂的)after the clarity of his words on screen; a secretary's tone seems more rejecting than I'd imagined it would be. Time itself becomes fluid- hours become minutes, and alternately seconds stretch into days. Weekends, once a highlight of my week, are now just two ordinary days. For the latest three years, since I stopped working as a producer for Charlie Rose, I have done much of my work as a telecommuter. I submit articles and edit them via E-mail and communicate with colleagues on Internet mailing lists. My boyfriend lives in England ; so much of our relationship is computer-mediated. If I desired, I could stay inside for weeks without wanting anything. I can order food, and manage my money, love and work. In fact, at times I have spent as long as three weeks alone at home, going out only to get mail and buy newspapers and groceries. I watched most of the blizzard of 1996 on TV. But after a while, life itself begins to feel unreal. I start to feel as though I've merged with my machines, taking data in, spitting them back, just another node on the net. Others on line report the same symptoms. We start to strongly dislike the outside forms of socializing. It's like attending an "AA" meeting in a bar with everyone holding a half sipped drink. We have become the net opponents' worst nightmare. What first seemed like a luxury, crawling from bed to computer, not worrying about hair, and clothes and faces, has become avoidance, a lack of discipline. And once you start replacing real human contact with cyber-interaction, coming back out of the cave can be quite difficult. At times, I turn on the television and just leave it to chatter in the background, something that I'd never done previously. The voices of the programs soothe me, but then I'm jarred by the commercials. I find myself sucked in by soap operas, or compulsively needing to keep up with the possible angle of every story over and over and over, even when they are of no possible use to me. Work moves from foreground to background.

单选题First Self-contained Heart Implanted A patient on the brink of death has received the world"s first self-contained artificial heart—a battery-powered device about the size of a softball that runs without the need for wires, tubes or hoses sticking out of the chest. Two surgeons from the University of Louisville implanted the titanium and plastic pump during a seven-hour operation at Jewish Hospital Monday. The hospital said the patient was "awake and responsive" Tuesday and resting comfortably. It refused to release personal details. The patient had been expected to die within a month without the operation, and doctors said they expected the artificial heart to extend the person"s life by only a month. But the device is considered a major step toward improving the patient"s quality of life. The new pump, called AbioCor, is also a technological leap from the mechanical hearts used in the 1980s, which were attached by wires and tubes to bulky machinery outside the body. The most famous of those, the Jarvic-7, used air as a pumping device and was attached to an apparatus about the size of a washing machine. "I think it"s potentially a major step forward in the artificial heart development," said Dr. David Faxon, president of the American Heart Association. However, he said the dream of an implantable, permanent artificial heart is not yet a reality, "This is obviously an experimental device whose long-term success has to be demonstrated." Only about half of the 4,200 Americans on a waiting list for donor hearts received them last year, and most of the rest died. Some doctors, including Robert Higgins, chairman of cardiology at the Medical College of Virginia in Richmond, said artificial hearts are unlikely to replace donor hearts. "A donor heart in a good transplant can last 15 to 30 years," he said. "It"s going to be hard to replace that with a machine." The AbilCor has a 2-pound pumping unit, and electronic controls that adjust the pumping speed based on the body"s needs. It is powered by a small battery pack worn outside the body that transmits current through the skin.

单选题I rarely wear a raincoat because I spend most of my time in a car. A. normally B. seldom C. continuously D. usually

单选题We have never seen such {{U}}gorgeous{{/U}} hills. A.beautiful B.stretching C.spreading D.rolling

单选题Tickets are limited and will be allocated to those who apply first. A. posted B. sent C. given D. handed

单选题Her overall language proficiency remains that of a toddler .

单选题Smoking is not permitted in the office.

单选题He notified his friends that his address had changed.