单选题The weather is a constant subject of conversation in Britain.

单选题The boats of the earliest voyagers to the North American continent were exceptionally well built.

单选题The steadily rising cost of labor on the waterfront has greatly increased the cost of shipping cargo by water.

单选题This is the identical room we stayed in last year.

单选题In judging our work you should take into consideration the fact that we have been very busy recently.

单选题We U explored/U the possibility of expansion at the conference．

单选题However bad the situation is, the majority is unwilling to risk change.

单选题IQ-gene In the angry debate over how much of IQ comes from the genes that children inherit from parents and how much comes from experiences, one little fact gets overlooked: no one has identified any genes (other than those that cause retardation) that affect intelligence. So researchers led by Robert Plomin of London"s Institute of Psychiatry decided to look for some. They figured that if you want to find a smart gene, you should look in smart kids. They therefore examined the DNA of students like those who are so bright that they take college entrance exams four years early—and still score at Princeton-caliber levels. The scientists found what they sought. "We have" says Plomin, "the first specific gene ever associated with general intelligence." Plomin"s colleagues drew blood from two groups of 51 children each, all 6 to 15 years old and living in six counties around Cleveland. In one group, the average IQ is 103. All the children are white. Isolating the blood cells, the researchers then examined each child"s chromosome 6. Of the 37 landmarks on chromosome 6 that the researchers looked for, one jumped out: a form of gene called IGF2R occurred in twice as many children in the high-IQ group as in the average group—32 percent versus 16 percent. The study, in the May issue of the journal Psychological Science, concludes that it is this form of the IGF2R gene that contributes to intelligence. Some geneticists see major problems with the IQ-gene study. One is the possibility that Plomin"s group fell for "chopsticks fallacy". Geneticists might think they"ve found a gene for chopsticks flexibility, but all they"ve really found is a gene more common in Asians than, say, Africans. Similarly, Plomin"s IQ gene might simply be one that is more common in groups that emphasize academic achievement. "What is the gene that they"ve found reflects ethnicity?" asks geneticist Andrew Feinberg of Johns Hopkins University. "That alone might explain the link to intelligence, since IQ tests are known for being culturally sensitive and affected by a child"s environment." And Neil Risch of Standford University points out that if you look for 37 genes on a chromosome, as the researchers did, and find that one is more common in smarter kids, that might reflect pure chance rather than a causal link between the gene and intelligence. Warns Feinberg: "I would take these findings with a whole box of salt."

单选题Tennessee possesses many caverns with gorgeous rock formations.A. beautifulB. largeC. significantD. flat

单选题Do you wake up every day feeling too tired, or even upset? If so, then a new alarm clock could bejust for you. The clock, called Sleep Smart, measures your sleep cycle, and waits for you to be in your lightest phase of sleep (51) rousing you. Its makers say that should (52) you wake up feeling refreshed every morning. As you sleep you pass (53) a sequence of sleep states - light sleep, deep sleep and REM (rapid eye movement)sleep - that (54) approximately every 90 minutes. The point in that cycle at which you wake can (55) how you feel later, and may even have a greater impact than how much or little you have slept. Being roused during a light phase means you are more likely to wake up energetic. Sleep Smart (56) the distinct pattern of brain waves (57) during each phase of sleep, via a headband equipped (58) electrodes (电极) and a microprocessor. This measures the electrical activity of the wearer' s brain, in much the (59) way as some machines used for medical and research (60) , and communicates wirelessly with a clock unit near the bed. You (61) the clock with the latest time at (62) you want to be wakened, and it then duly (适时地) wakes you during the sleep phase before that. The (63) was invented by a group of students at Brown University in Rhode Island (64) , a friend complained of waking up tired and performing poorly on a test. "As sleep -deprived people ourselves, we started thinking of (65) to do about it," says Eric Shashoua, a recent college graduate and now chief executive officer of Axon Sleep Research Laboratories, a company created by the students to develop their idea.

单选题Call American Their names A great difference between American social customs and those of other countries is the way in which names are used. Americans have little concern for "rank", especially socially. Most Americans do not want to be treated in any especially respectful way because of their age or social rank ; it makes them feel uncomfortable. Many Americans even find the terms "Mr. ", "Mrs. " or "Miss" too formal. People of all ages may prefer to be called by their first names. "Don't call me Mrs. Smith. Just call me Sally. " Using only first names usually indicates friendliness and acceptance. However, if you do not feel comfortable using only first names, it is quite acceptable to be more for mal. Just smile and say that after a while you will use first names but you are accustomed to being more when you first meet someone. Very often, introductions are made using both first and last names: "Mary Smith, this is John Jones. " In this situation you are free to decide whether to call the lady "Mary" or "Miss Smith".Sometimes both of you will begin a conversation using last names, and after a while one or both of you may begin using first names instead. You have a choice : if you don't want to use first names so quickly, no one will think it impolite if you continue according to you own custom.

单选题Learning to Forgive To forgive may be divine, but no one ever said it was easy. When someone has deeply hurt you, it can be extremely difficult to let go of your grudge . But forgiveness is possible, and it can be surprisingly beneficial to your physical and mental health. "People who forgive show less depression, anger and stress and more hopefulness," says Frederic Luskin, Ph. D. , author of Forgive for Good. "So it can help save on the wear and tear on our organs, reduce the wearing out of the immune system and allow people to feel more vital." So how do you start the healing? Try following these steps: Calm yourself. To defuse your anger, try a simple stress-management technique. "Take a couple of breaths and think of something that gives you pleasure: a beautiful scene in nature, or someone you love," Luskin says. Don"t wait for an apology. "Many times the person who hurt you has no intention of apologizing," Luskin says. "They may have wanted to hurt you or they just don"t see things the same way. So if you wait for people to apologize, you could be waiting an awfully long time." Keep in mind that forgiveness does not necessarily mean reconciliation with the person who upset you or condoning of his or her action. Take the control away from your offender. Mentally replaying your hurt gives power to the person who caused you pain. "Instead of focusing on your wounded feelings, learn to look for the love, beauty and kindness around yon," Luskin says. Try to see things from the other person"s perspective. If you empathize with that person, you may realize that he or she was acting out of ignorance, fear, even love. To gain perspective, you may want to write a letter to yourself from your offender"s point of view. Recognize the benefits of forgiveness. Research has shown that people who forgive report more energy, better appetite and better sleep patterns. Don"t forget to forgive yourself. "For some people, forgiving themselves is the biggest challenge," Luskin says. "But it can rob you of your self-confidence if you don"t do it."

单选题A lot of people could fall ill after drinking contaminated water.

单选题The passage indicates that spending more money on disease prevention will mean

单选题She shows little regard for the feelings of others and does exactly what she wants to.

单选题{{B}}第三篇{{/B}} {{B}}Giving Up Smoking{{/B}} A number of devices are available to help a person quit smoking. Nicotine (尼古丁) patches are small, nicotine-containing adhesive (粘着性的) discs applied to the skin. The nicotine is slowly absorbed through the skin and enters the bloodstream (血流). Over time, the nicotine dose is reduced and eventually the desire for nicotine is eased. Nicotine gum (口香糖) works in a similar manner, providing small doses of nicotine when chewed (咀嚼). The benefits of giving up smoking include the immediate reduction of harm to the health of the smoker and easier admission to social activities and institutions that ban smoking. In a 1988 report, the U.S. Surgeon General declared cigarette smoking to be more harmful and expensive than the use of cocaine (可卡因), alcohol, or heroin. Recent evidence supports this claim. The United States government has collected a special tax on cigarettes for several decades. The rate rose from 8 cents per pack of 20 cigarettes in 1951 to 24 cents per pack in 1993. In other developed countries, the cigarette tax rate is much higher, ranging from 50 percent in Switzerland to 85 percent in Denmark. In the United States, the first direct action to check smoking was the regulation of a warning on cigarette packages by the Federal Trade Commission. This warning took effect in 1964 and was strengthened in 1969 to read: "Warning: The Surgeon General Has Determined That Cigarette Smoking Is Dangerous to Your Health." In 1971 all cigarette advertising was banned from radio and television, and cities and states passed laws requiring nonsmoking sections in public places and workplaces.

单选题The weather is a constant subject of conversation in Britain.

单选题Human facial expression differ from those of animals in the degree to which they can be Udeliberately/U controlled and modified.

单选题 Thirst for Oil Worldwide every day, we devour the energy equivalent of about 200 million barrels of oil. Most of the energy on Earth comes from the Sun. In fact enough energy from the Sun hits the planet's surface each minute to cover our needs for an entire year, we just need to find an efficient way to use it. So far the energy in oil has been cheaper and easier to get at. But as supplies dwindle, this will change, and we will need to cure our addiction to oil. Burning wood satisfied most energy needs until the steam-driven industrial revolution, when energy-dense coal became the fuel of choice. Coal is still used, mostly in power stations, to cover one quarter of our energy needs, but its use has been declining since we started pumping up oil. Coal is the least efficient, unhealthiest and most environmentally damaging fossil fuel, but could make a comeback, as supplies are still plentiful; its reserves are five times larger than oil's. Today petroleum, a mineral oil obtained from below the surface of the Earth and used to produce petrol, diesel oil and various other chemical substances, provides around 40% of the world's energy needs, mostly fuelling automobiles. The U.S. consumes a quarter of all oil, and generates a similar proportion of greenhouse gas emissions. The majority of oil comes from the Middle East, which has half of known reserves. But other significant sources include Russia, North America, Norway, Venezuela and the North Sea. Alaska's Arctic National Wildlife Refugel could be a major new U.S. source, to reduce reliance on foreign imports. Most experts predict we will exhaust easily accessible reserves within 50 years, though opinions and estimates vary. We could fast reach an energy crisis in the next few decades, when demand exceeds supply. As conventional reserves become more difficult to access, others such as oil shales and tar sands may be used instead. Petrol could also be obtained from coal. Since we started using fossil fuels, we have released 400 billion tonnes of carbon, and burning the entire reserves could eventually raise world temperatures by 13℃. Among other horrors, this would result in the destruction of all rainforests and the melting of all Arctic ice.

单选题Soldiers have to Uobey/U orders.