单选题He endured great pain before he finally expired .

单选题{{B}}第三篇{{/B}} {{B}}Smart Exercise{{/B}} Doctors are starting to find more and more information that suggests a connection between exercise and brain development. Judy Cameron, a scientist at Oregon Health and Science University, studies brain development. According to her research, it seems that exercise can make blood vessels, including those in the brain, stronger and more fully developed. Dr. Cameron claims this allows people who exercise to concentrate better. As she says: "While we already know that exercise is good for the heart, exercise can literally cause physical changes in the brain." The effects of-exercise on brain development can even be seen in babies. Babies who do activities that require a lot of movement and physical activity show greater brain development than babies who are less physically active. With babies, even a little movement can show big results. Margaret Barnes, a pediatrician (儿科医师), believes in the importance of exercise. She thinks that many learning disabilities that children have in elementary school or high school can be traced back to a lack of movement as babies. "Babies need movement that stimulates their five senses. They need to establish a connection between motion and memory. In this way, as they get older, children will begin to associate physical activity with higher learning," says Margaret. Older people can beef up their brains as well. Cornell University studied a group of seniors ranging in age from seventy to seventy-nine. Their study showed a short-term memory increase of up to 40 percent after exercising just three hours a week. The exercise does not have to be very difficult, but it does have to increase the heart rate. Also, just like the motion for infants, exercise for older people should involve some complexity. Learning some new skills or motions helps to open up memory paths in the brain that may not have been used for a long time. For most people, any type of physical activity that increases the heart rate is helpful. The main goal is to increase the brain's flow of blood. And your brain can benefit from as little as two to three hours of exercise a week.

单选题The benzene molecule contains six carbon atoms joined together in the form of a six-sided ring.A. representedB. connectedC. containedD. included

单选题Need for Emphasis on Treatment AIDS programs in developing countries put too little emphasis on treatment, the World Health Organization said Tuesday, asking for more small community-based clinics to be opened to treat HIV-infected people. An estimated 36 million to 46 million people are living with AIDS, two-thirds of them in Africa, but only 440,000 people in developing countries were receiving treatment by the end of 2003, the UN health agency said in its annual report. "Without treatment, all of them will die a premature and in most cases painful death," the WHO said in the 169-page World Health Report. WHO Director General Lee Jong-wook said community-based treatment should be added to disease prevention and care for sufferers in AIDS programs. "Future generations will judge our time in large part by our response to the AIDS disease," Lee said. "By tackling it decisively we will also be building health systems that can meet the health needs of today and tomorrow. This is a historic opportunity we cannot afford to miss," he added. Antiretroviral drugs enable people hit by AIDS to live longer. The annual cost of treatment, which was about $10,000 when the drugs were first developed, has dropped to about $150. Treatment programs also help AIDS prevention efforts, the report said, citing great demands for testing and counseling where treatment has been made available. Good counseling in turn leads to more effective prevention in those who are uninfected, and significantly reduces the potential for HIV carriers to pass on the infection, the report said. Since its discovery in the 1980s, more than 20 million have died of AIDS, mostly in poor countries.

单选题Don"t hazard your reputation by supporting his joint venture with the gay from Los Angels.

单选题It has been said that the Acts provided a new course of action and did not merely regulate or enlarge an old one.

单选题 Many Women Who Beat Cancer Don't Change Habits Many women who battle breast cancer will tell you it's a life-changing experience. However, a new study shows that for many {{U}} {{U}} 1 {{/U}} {{/U}}, the changes aren't always positive or permanent. Beth Snoke has watched her mother and both grandmothers battle and survive breast {{U}} {{U}} 1 {{/U}} {{/U}}. So when she was diagnosed, there was no doubt in her mind {{U}} {{U}} 3 {{/U}} {{/U}}she had to do. "I do exactly what the doctors say as far as the medicine that I'm on, as {{U}} {{U}} 4 {{/U}} {{/U}}as the vitamins, the diet, and the fitness. And I can't stress enough {{U}} {{U}} 5 {{/U}} {{/U}}important that is," says Beth Snoke. But a surprising new study shows that {{U}} {{U}} 6 {{/U}} {{/U}}every woman who beats breast cancer is getting that message. In fact, nearly 40% of them say even {{U}} {{U}} 7 {{/U}} {{/U}}surviving breast cancer, they haven't made significant changes in the {{U}} {{U}} 8 {{/U}} {{/U}}they eat or how much they exercise. "Not all survivors are taking advantage of this teachable moment and making positive health changes in {{U}} {{U}} 9 {{/U}} {{/U}}life," says Electra Paskett, PhD, at Ohio State University's Comprehensive Cancer Center. Paskett says diet and exercise have been proven to not only help women feel better during and after treatment, they may {{U}} {{U}} 10 {{/U}} {{/U}}play a role in preventing some cancers from coming back. {{U}} {{U}} 11 {{/U}} {{/U}}growing evidence, some women just aren't listening. "Colon cancer survivors {{U}} {{U}} 12 {{/U}} {{/U}}exercise have actually been shown to have improved survival rates. So, yes, it is true that perhaps by making some of these healthy choices we can actually increase their health," says Paskett. As a breast cancer survivor {{U}} {{U}} 13 {{/U}} {{/U}}, Paskett knows first hand how much difference diet and exercise can {{U}} {{U}} 14 {{/U}} {{/U}}. The challenge, she says, is to get more survivors to be more like Beth, during and after treatment. Experts say exercising more and eating a healthier diet can also cut {{U}} {{U}} 15 {{/U}} {{/U}}on stress and help women overcome depression. There are more than 2 million breast cancer survivors living in the U.S. of those, nearly a million have yet to change their diet or exercise routines.

单选题I had some difficulty in carrying out the plan.

单选题 阅读下面这篇短文，短文后列出了7个句子，请根据短文的内容对每个句子作出判断。如果该句提供的是正确信息，请选择A项；如果该句提供的错误信息，请选择B项；如果该句的信息文章中没有提及，请选择C项。 {{B}} Stomach Ulcer{{/B}} Stomach ulcers are the cause of severe pain for many people. Doctors have been able to help lessen the pain of ulcers. They could not cure them. Now doctors have discovered a cause of ulcers. This means they may have found a way to cure people who suffer from the stomach pain. Studies show that ten percent of the population will develop an ulcer at some time in their life. So a possible cure is good news for many people. Ulcers are wounds in the stomach that are similar to small cuts or tears. These wounds can harm the tissue in the stomach, the pipe that carries the food to the stomach or parts of the small intestines. Fluids in the stomach then increase the pain of an ulcer. How does a person know he or she has an ulcer? Doctors say most people with ulcers feel a burning pain in their chest or stomach. This pain often is called heart bum. It usually happens before eating or during the night. It causes some people to lose their desire to eat, or they are unable to keep food in their stomachs. Doctors believed that ulcers were caused by unusually strong stomach fluids, which damaged stomach tissue. Now they have discovered that most ulcers are caused by a bacterial organism called Hillico Bactor Pilorie or H. Pillorie. H. Pillorie bacteria are what make stomach produce extra stomach fluid. Doctors found that they can kill the bacteria with medicines called antibiotics. Health experts say the discovery of a cure for ulcers an save thousands of millions of dollars in medical costs. They also believe curing ulcers will reduce the number of people who develop stomach cancer. The number of people with stomach cancer is very high in Japan, Southeast Asia and parts of Africa. Doctors say a person is more likely to get an ulcer if his or her family has had one. In fact a person with the family history of ulcers is three times more likely to get one than other people. There are ways people can protect themselves from developing an ulcer. Doctors say it is more important to reduce the amount of strong fluids in the stomach. To do this, doctors say, people should not smoke cigarettes or drink alcohol. And they say people should reduce tension in their lives.

单选题I positively believe that there' s been no mistake.A. rationallyB. reasonablyC. certainlyD. boundly

单选题It is pleased for me to have met you here.A. a pityB. gladC. sadD. unwilling

单选题Greene spent a brief time at Cambridge.A. shortB. hardC. goodD. long

单选题 Plant Gas Scientists have been studying natural sources of methane for decades but hadn't regarded plants as a producer, notes Frank Keppler, a geochemist at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany. Now Keppler and his colleagues find that plants, from grasses to trees, may also be sources of the greenhouse gas. This is really surprising, because most scientists assumed that methane production requires an oxygen-free environment. Previously, researchers had thought that it was impossible for plants to make significant amounts of the gas. They had assumed that, microbes need to be in environments without oxygen to produce methane. Methane is a greenhouse gas, like carbon dioxide. Gases such as methane and carbon dioxide trap heat in Earth's atmosphere and contribute to global warming. In its experiments, Keppler's team used sealed chambers that contained the same concentration of oxygen that Earth's atmosphere has. They measured the amounts of methane that were released by both living plants and dried plant material, such as fallen leaves. With the dried plants, the researchers took measurement at temperatures ranging from 30℃ to 70℃. At 30℃, they found, a gram of dried plant material released up to 3 nanograms of methane per hour. (One nanogram is a billionth of a gram.) With every 10-degree rise in temperature, the amount of methane released each hour roughly doubled. Living plants growing at their normal temperatures released as much as 370 nanograms of methane per gram of plant tissue per hour. Methane emissions tripled when living and dead plant was exposed to sunlight. Because there was plenty of oxygen available, it's unlikely that the types of bacteria that normally make methane were involved. Experiments on plants that were grown in water rather than soil also resulted in methane emissions. That's another strong sign that the gas came from the plants and not soil microbes. The new finding is an "interesting observation", says Jennifer Y. King, a biogeochemist at the University of Minnesota in St. Paul. Because some types of soil microbes consume methane, they may prevent plant-produced methane from reaching the atmosphere. Field tests will be needed to assess the plant's influence, she notes.

单选题Fine freshwater pearls are found in the main stream and the tributaries of the Mississippi River.______

单选题About one quarter of the workers in the country are employed in factories.

单选题______ they can do to help us is not known.A. whatB. whenC. thatD. where

单选题He paid the boy 10 dollars for washing ten windows, most of ______ hadn't been cleaned.A. theseB. thoseC. thatD. which

单选题The motorcar Some pessimistic experts feel that the automobile is bound to fall into disuse. They see a day in the not-too-distant future when all autos will be abandoned and allowed to rust. Other authorities, however, think the auto is here to stay. They hold that the car will remain a leading means of urban travel in the foreseeable future. The motorcar will undoubtedly change significantly over the next 30 years. It should become smaller, safer, and more economical, and should not be powered by the gasoline engine. The car of the future should be far more pollution-free than present types. Regardless of its power source, the auto in the future will still be the main problem in urban traffic congestion. One proposed solution to this problem is the automated highway system. When the auto enters the highway system, a retractable (可伸缩的) arm will drop from the auto and make contact with a rail, which is similar to those powering subway trains electrically. Once attached to the rail, the car will become electrically powered from the system, and control of the vehicle will pass to a central computer. The computer will then monitor all of the car's movements. The driver will use a telephone to dial instructions about his destination into the system. The computer will calculate the best route, and reserve space for the car all the way to the correct exit from the highway. The driver will then be free to relax and wait for the buzzer (蜂鸣器) that will waru him of his coming exit. It is estimated that an automated highway will be able to handle 10,000 vehicles per hour, compared with the 1,500 to 2,000 vehicles that can be carried by a present-day highway.

单选题{{B}}第三篇{{/B}} {{B}} Adaptation of Living Things{{/B}} Certain animals and plants develop characteristics that help them cope with their environment better than others of their kind. This natural biological process is called adaptation. Among the superior characteristics developed through adaptation are those that may help in getting food or shelter, in providing protection, and in producing and protecting, the young. That results in the evolution of more and more organisms that are better fitted to their environments. Each living thing is adapted to its way of life in a general way, but each is adapted especially to its own distinct class. A plant, for example, depends upon its roots to fix itself firmly and to absorb water and inorganic chemicals. It depends upon its green leaves for using the sun's energy to make food from inorganic chemicals. These are general adaptations, common to most plants. In addition, there are special adaptations that only certain kinds of plants have. Many animals have adaptations that help them escape from their enemies, Some insects are hidden by their body color or shape, and many look like steal or a little branch. The coats of deer are colored to mix with the surroundings. Many animals have the ability to remain completely still when an enemy is near. Organisms have a great variety of ways of adapting. 'They may adapt in their structure, function, and genetics; in their development and production of the young; and in other respects. An organism may create its own environment, as do warm-blooded mammals, which have the ,ability to adjust body heat exactly to maintain their ideal temperature' despite changing weather; Usually adaptations are an advantage, but sometimes an organism is so well adapted to a particular, environment that, if conditions change, it finds it difficult or impossible to readapt to the new conditions;

单选题Einstein's theory of relativity seemed incredible when it was first introduced.A. brilliantB. complicatedC. unbelievableD. distinguished