单选题The Polynesians found uses for many indigenous plants.

单选题 Where Have All the Frogs Gone? In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物) are declining or have become extinct. They have been around for a long time - over 350 million years. Why are they dying out now? Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledge. By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear. The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the earth is becoming unlivable for amphibians, is it also becoming unlivable for other kinds of animals and human, beings as well? Scientists now believe that amphibian decline is due to several environmental factors. One of these factors is the destruction of habitat, the natural area where an animal lives. Amphibians are very sensitive to changes in their habitat. If they cannot find the right conditions, they will not lay their eggs. These days, as wild areas are covered with houses, roads, farms, or factories, many kinds of amphibians are no longer laying eggs. For example, the arroyo toad (蟾蜍) of southern California will only lay its eggs on the sandy bottom of a slow-moving stream. There are very few streams left in southern California, and those streams are often muddy because of building projects. Not surprisingly, the arroyo toad is now in danger of extinction. There are a number of other factors in amphibian decline. Pollution is one of them. In many industrial areas, air pollution has poisoned the rain, which then falls on ponds and kills the frogs and toads that live there. In farming areas, the heavy use of chemicals on crops has also killed off amphibians. Another factor is that air pollution has led to increased levels of ultraviolet (UV) light. This endangers amphibians, which seem to be especially sensitive to UV light. And finally, scientists have discovered a new disease that seems to be killing many species of amphibians in different parts of the world. All these reasons for the disappearance of amphibians are also good reasons for more general concern. The destruction of land, the pollution of the air and the water, the changes in our atmosphere, the spread of diseases - these factors affect human beings, too. Amphibians are especially sensitive to environmental change. Perhaps they are like the canary (金丝雀) bird that coal miners once used to take down into the mines to detect poisonous gases. When the canary became iii or died, the miners knew that dangerous gases were near and their own lives were in danger.

单选题John is collaborating with Mary in writing an article.

单选题The word "Sunset" in the title of this novel most 'probably means

单选题What were the consequences of the decision she had made?

单选题They have the capability to destroy the enemy in a few days. A．possibility B．necessity C．ability D．probability

单选题Of all the planets in this solar system, Mercury is nearest the Sun. A. most like B. closest to C. hotter than D. heavier than

单选题 下面有3篇短文，每篇短文后有5道题，每道题后面有4个选项。{{B}}第一篇{{/B}} {{B}}Obesity (肥胖): the Scourge (祸害) of the Western World{{/B}} Obesity is rapidly becoming a new scourge of the western world, delegates agreed at the llth European Conference on the issue in Vienna Wednesday to Saturday. According to statements before the opening of the conference — of 2,000 specialists from more than 50 countries — 1.2 billion people worldwide are overweight, and 250 million are obese. Professor Bernhard Ludvik of Vienna General Hospital said," Obesity is a chronic illness. In Germany, 20 per cent of the people are already affected, but in Japan only one per cent." But he said that there was hope for sufferers thanks to the new scientific discoveries and medication. Professor Friedrich Hopichler of Salzberg said, "We are living in the new age (but) with the metabolism of a stone — age man." "I have just been to the United States. It is really terrible. A pizza shop is springing up on every comer. We have been overran by fast food and Coca-Cola-ization." Many of the experts stressed that obesity was a potential killer. Hopichler said," Eighty per cent of all diabetics are obese, also fifty per cent of all patients with high blood pressure and fifty per cent with adipose tissue complaints." "Ten per cent more weight means thirteen per cent more risk of heart disease. Reducing one's weight by ten per cent leads to thirteen per cent lower blood pressure." Another expert Hermann Toplak said that the state health services should improve their financing of preventive programs. "Though the health insurance pays for surgery (such as reducing the size of the stomach) when the body-mass index is more than 40. That is equivalent to a weight of 116 kilograms for a height of 1.70 meters. One should start earlier." Ludvik said that prevention should begin in school. "Child obesity (fat deposits) correlates with the time which children spend in front of TV sets." The consequences were only apparent later on. No more than fifteen per cent of obese people lived to the average life expectancy for their population group. scourge n. 天灾;祸害 obesity n. 肥胖症 overrun vt. 侵扰；蹂躏 obese adj. 肥胖症 diabetic n. 糖悄病患者；adj.糖尿病的 medication n. 药物疗法 adipose adj.脂肪的；肥胖的 metabolism n.新陈代谢

单选题The police took fingerprints and identified the body.

单选题Solar Storm At the end of October 2003, a sudden solar storm hit the earth. A solar storm refers to the large amounts of charged particles released into space 1 the solar energy increases. The release of the energy 2 place along with the activity of the sunspots with a cycle of 11 years. This time, the 3 of the storm exceeded expectations. This 4 of intense solar storm was caused by the eruption of a solar flare (闪光) and the ejection (喷发) of the solar corona (日寇) on October28, 2003. Large amounts of charged particles moved 150, 000, 000 kilometers through space toward the 5 in 19 hours. They could affect aircraft roaming (漫游) in space. The high-energy particles will 6 some of the parts of an aircraft. They may also cause it to fail. High-energy particles can threaten the safety of an aircraft at a high orbit. If an aircraft orbits at a lower orbit, it is 7 because it is under the protection of the earth"s magnetic field. A solar storm not only affects aircraft but also is a 8 to the environment and humans. The aerosphere and magnetic field of the earth can 9 humans from ultraviolet radiation and X-rays. While most of the X-rays are absorbed after they enter the aerosphere (大气层), still a few can 10 the ground. The geomagnetic storm caused by this round of solar storm reaches its highest level on the two 11 of the earth, which affects electricity supply of North America. Overexposure to 12 threatens the health of passengers on planes flying over the Polar Regions. If we fly in the sky during such a solar storm, it 13 we receive ten times the X-ray radiation. It"s really damaging. Scientists say a solar eruption is like the sun sneezing, which will make the earth 14 a cold. Though this natural force is irresistible, scientists can still 15 its movement accurately by monitoring. Facing successive solar storms, humans can"t drop their guard.

单选题The Cold Places The Arctic is a polar region. It surrounds the North Pole. Like Antarctica, the Arctic is a land of ice and snow. Antarctica holds the record for a low temperature reading—125 degrees Fahrenheit below zero. Reading of 85 degrees below zero is common in both the Arctic and Antarctica. Winter temperatures average 30 degrees below zero in the Arctic. At the South Pole the winter average is about 73 degrees below zero. One thing alone makes it almost impossible for men to live in Antarctica and in parts of the Arctic. This one thing is the low temperature-the killing chill of far North and the polar South. To survive, men must wear the warmest possible clothing. They must build windproof shelters. They must keep heaters going at all times. Not even for a moment can they be unprotected against the below-zero temperatures. Men have a way of providing for themselves. Polar explorers wrap themselves in warm coats and furs. The cold makes life difficult. But the explorers can stay alive. What about animals? Can they survive? Do we find plants? Do we find life in the Arctic and in Antarctica? Yes, we do. There is life in the oceans. There is life on land. Antarctica, as we have seen, is a cold place indeed. But this has not always been the case. Expedition scientists have discovered that Antarctica has not always been a frozen continent. At one time the weather in Antarctica may have much like our own. Explorers have discovered coal in Antarctica. This leads them to believe that Antarctica at one time was a land of swamps and forests. Heat and moisture must have kept the trees in the forests alive.

单选题Experts at Marshall Space Flight Center in Huntsville, Alabama, have been working for years on a successor to the shuttle. The project, known as the Space Launch Initiative, was divided into two parts-one focusing on a further launch vehicle, the other on a space station orbiter. The orbiter is expected to be ready sooner. The program's manager say NASA officials have told them not to alter Space Launch Initiative in light of the Columbia disaster. US President George W. Bush asked Congress for about US $1 billion for Space Launch Initiative in 2004, funds that would be almost equally split between the Orbital Space Plane and Next Generation Launch Technology. How much fund would the Orbital Space Plane probably get?A. US $1 billionB. US $ 2 billionC. US $ 50 millionD. Not mentione

单选题Proper exercise plays a significant role in the {{U}}rehabilitation{{/U}} of patients with various back ailments.

单选题It is taken for granted that a piano without any defects would produce very grand music.A. dislikesB. incidentsC. faultsD. merits

单选题Although the men' s movement and the anxiety it expresses are city-based, the Udispute/U is widespread.

单选题The police arrested the suspect yesterday and released him this morning.

单选题Peking is a densely populated area.

单选题Don't Treat Animals as Furry Test-tubes Most of us agree that there is a moral obligation to minimize the suffering of any captive animals. In addition, there are numerous self-serving reasons why we should respect the welfare of our captive companions. However, the impact of poor animal welfare on the quality of animal science always concerns a scientist the most. Rodents(灵长类动物) make up over 80% of the animals used in scientific procedures, and most are kept in small, barren cages. Such housing is known to constrain normal development, affecting the structure and function of adult rodent brains. These rodents may spend 50% of waking hours performing repetitive activities without apparent purpose. This abnormal behavior is likely to reflect what is going on inside the body. As ethnologist Hanno Wfirbel, of the Justus Liebig University of Giessen, Germany, puts it," The point that the environment might change behavior but it doesn't change biology is ridiculous. Every behavior has a physiological background." If welfare affects behavior, and therefore biology, it will affect scientific outcomes. As long as we continue to treat experimental animals as simple" furry test-tubes", ignoring their abilities and needs, we endanger the quality of the work we do with them. So, how can we improve life for other species when we cannot experience it as they do? We'd better ask the animals. Ask them what they need, and what causes them suffering, through carefully designed preference tests and in-depth behavioural research. Scientists have already begun this task, and have been told some important and unexpected facts by their study subjects. By consistently self-medicating with pain killers, broiler chickens (嫩鸡) have told us that they are in chronic pain. By moving a barrier twice their size, mink (水貂) have told us that water baths are the most important enrichment for them. By only stopping their fruitless stereotypic digging in certain circumstances, gerbils(沙鼠) have told us that they need to be able to sleep in tunneled nest-boxes. By behaving normally again, starlings have told us that they need high frequency light bulbs.

单选题The courageous boy has been the subject of Umassive/U media coverage．

单选题The food is insufficient for three people.