单选题The attack on Fort Sumter near Charleston provoked a sharp response from the North, which led to the American Civil War.

单选题And the cars are tested for defects before leaving the factory.

单选题He has established himself to be a Ucompetent/U manager by his successfully handling several difficult tasks.

单选题Her novel depicts an ambitious Chinese. A．writes B．sketches C．describes D．indicates

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Dangerous Sunshine to Children Two United Nations agencies warned on Tuesday that children are most at risk of developing skin cancers as a result of the long-term decline in the earth"s protective ozone layer. The agencies, the World Health Organization (WHO) and the UN Environmental Programme (UNEP), issued the warning as they launched a global programme aimed at alerting schools to the dangers of exposure to the sun. "As ozone depletion becomes more marked, and as people around the world engage more in sun seeking behaviour, the risk of health complications from over-exposure to ultraviolet radiation is becoming a substantial public health concern," said WHO Directorgenera Lee Jong-wook. By reducing the time children and adolescents are exposed to direct sunlight, he said. "We can substantially reduce the risk of contracting skin cancers, cataracts and other conditions which might only appear much later in life." In its 2002 World Health Report, the WHO said around the world an average of 66,000 people died every year from melanoma or other types of skin cancer. Independent scientific research shows that every year there are between two to three million new cases of non-malignant melanoma and around 130,000 malignant—and normally fatal—new full blown skin cancer cases. Although most known skin cancers seemed to occur in the industrialized world, WHO radiation and environmental health specialist Mike Repacholi told a news conference, there were many cases believed to be unreported in poorer countries. Although people with darker skins were less susceptible to skin cancers, they were just as likely to contract eye cataracts as fairer-skinned populations, and people living close to the equator were even more likely to develop them. As for the protection method, the WHO said that under the school plan, dubbed the Inter Sun Project, the two agencies will distribute packages showing teachers how to develop their own sun education programmes, the WHO said. In a joint statement from the two agencies which also marked the International Day for the Preservation of the Ozone Layer, UNEP Executive Director Klaus Toepfer said latest studies showed the protective shield was on the road to recovery. This was the result of international agreements over the past two decades to phase out use of various chemicals—like those used in some pesticides, refrigerators and aerosols. "But we must remain vigilant and more needs to be done before we can say that the problem is solved for good," said Toepfer. This included stopping illegal trade in banned chemicals and enforcing the agreements in developing countries. "Only then can we say that the sky above our heads will be safe for our children and their children to come," the former German environment minister said.

单选题My brother' s plans are very ambitious.A. arbitraryB. aggressiveC. adequateD. abundant

单选题The river Uwidens/U considerably as it begins to turn west.

单选题Firewood is scarce in many parts of the world.A. hard to sellB. easy to makeC. hard to findD. easy to store

单选题Techniques to {{U}}harness{{/U}} the energy of the sun are being developed. A.convert B.store C.utilize D.receive

单选题Going Back to Its Birthplace No sporting event takes hold of the world"s attention and imagination like the Olympic Games. The football World Cup fascinates fans in Europe and South America: the baseball"s World Series is required viewing in North America: the World Table Tennis Championships attracts the most interest in Asia. But the Olympics belong to the whole world. Now, after travelling to 17 countries over 108 years, the Summer Games are returning to Athens, the place where the first modern Olympics was held. Participation in the Games is looked on not only as an achievement, but also as an honor. The 16 days between August 13 and 29 will see a record—202 countries compete, up from Sydney"s 199. Afghanistan is back, having been banned from Sydney because the Taliban government didn"t let women do sports. There is also a place for newcomers East Timer and Kiribati. A total of 10,500 athletes will compete in 28 sports, watched by 53 million ticket-paying viewers as well as a television audience of 4 billion. Athens is to use its rich history and culture to make the Olympics as special as possible. The Games will open with cycling events which start in front of the Parthenon and Acropolis monuments. The final event will be a historic men"s marathon following the original route run by Phidippides in 490 B.C. to bring news of victory over the Persians. The ancient stadium at Olympia, first used for the Games nearly three centuries ago, will stage the shot put competitions. And the Panathenian Stadium, where the first modern Olympics was held, is to host the archery (射箭) events. If the well-known ancient sites deliver a great sense of history to the Games, the 39 new venues add a modern touch to the city of Athens. The main Olympic stadium, with a giant glass and steel roof, is the landmark (标志) building of the Olympics. "We believe that we will organize a "magical" Games," said Athens 2004 President Gianna Angelopoulos Daskalaki. "Our history with the Olympic Games goes back nearly 3,000 years, and Athens 2004 could be the best ever."

单选题The secretary is expected to explore ideas for post-war reconstruction of the area.

单选题These are defensive behavior patterns which derive from our fears.

单选题Crystal Ear One day a friend asked my wife Jill if I wanted a hearing aid. "He certainly does," replied Jill. After hearing about a remarkable new product, Jill finally got up the nerve to ask me if I"d ever thought about getting a hearing aid. "No way," I said. "It would make me look 20 years older. No, no," she replied. "This is entirely different. It"s Crystal Ear!" Jill was right. Crystal Ear is different—not the old-styled body worn or over-the-ear aid, but an advanced personal sound system so small that it"s like contacts (隐形眼镜) for your ears. And Crystal Ear is super-sensitive and powerful, too. You will hear sounds your ears have been missing for years. Crystal Ear will make speech louder, and the sound is pure and natural. I couldn"t believe how tiny it is. It is smaller than the tip of my little finger and it"s almost invisible when worn. There are no wires, no behind-the-ear device. Put it in your ear and its ready-to-wear mold (形状) fits comfortably. Since it"s not too loud or too tight, you may even forget that you"re wearing it! Use it at work or at play. And if your hearing problem is worse in certain situations, use Crystal Ear only when you need it. Hearing loss, which occurs typically prior to teenage years, progresses throughout one"s lifetime. Although hearing loss is now the world"s number one health problem, nearly 90 percent of people suffering heating loss choose to leave the problem untreated. For many millions, treating hearing loss in a conventional way can involve numerous office visits, expensive testing and adjustments to fit your ear. Thanks to Crystal Ear, the "sound solution" is now convenient. Almost 90 percent of people with mild hearing loss, and millions more with just a little hearing drop-off (下降), can be dramatically helped with Crystal Ear. Moreover, its superior design is energy-efficient, so batteries can last months. Crystal Ear is now available to help these people treat their hearing loss with a small hearing amplifier(放大器).

单选题 Common-cold Sense You can't beat it, but you don't have to join it. Maybe it got the name "common cold" because it's more common in winter. The fact is, though, being cold doesn't have anything to do with getting one. Colds are caused by the spread of rhinoviruses, and, at least so far, medical science is better at telling you how to avoid getting one than how to get rid of one. Children are the most common way cold viruses are spread to adults, because they have more colds than adults—an average of about eight per year. Why do kids seem so much more easily to get colds than their parents? Simple. They haven't had the opportunity to become immune to many cold viruses. There are more than 150 different cold viruses, and you never have the same one twice. Being infected by one makes you immune to it—but only it. Colds are usually spread by direct contact, not sneezing or coughing. From another person's hand to your hand and then to your nose or eyes is the most common route. The highest concentration of cold viruses anywhere is found under the thumbnails of a boy, although the viruses can survive for hours on skin or other smooth surfaces. Hygiene is your best defense. Wash your hands frequently, preferably with a disinfectant soap, especially when children in your household have colds. But even careful hygiene won't ward off every cold. So, what works when a coughing, sneezing, runny nose strikes? The old prescription of two aspirins, lots of water, and bed rest is a good place to start. But you'll also find some of the folk remedies worth trying. Hot mixtures of sugar (or honey), lemon, and water have real benefits.

单选题Dried Foods Centuries ago, man discovered that removing moisture (51) food helped to preserve it, and that the easiest way to do this was to expose the food to the sun and wind. In this (52) the North American Indians produce dried meat and make it into cakes, the Scandinavians make (53) fish and the Arabs make dried dates. All foods contain (54) , cabbage and other leaf vegetables contain as much as 93% water, potatoes and other root vegetables 80%, lean meat 75%, and fish anything from 80% to 60% depending (55) how fatty it is. If this water is (56) , the activity of the bacteria which causes food to go bad is stopped. Now day most foods are dried mechanically. The most common () of such drying is to put food in chambers. This is the usual method for drying such things (58) vegetables, minced meat, and fish. Liquids such as milk, coffee, tea, soups and eggs may be dried (59) pouring them over a heated horizontal steel cylinder or by spraying them into a chamber through (60) a current of hot air passes. In the first (61) , the dried material is scraped off the roller as a thin film which is then broken up into small pieces, though still relatively coarse flakes. In the second process it fails to the bottom of the chamber as a fine powder. Where (62) pieces of meat and vegetables are required, as in soup, the ingredients are dried separately and then mixed. Dried foods take up less room and weigh less (63) the same food packed in can or frozen, and they are (64) to climbers, explorers and soldiers in battle, who have little storage space. They are also popular with housewives (65) it takes so little time to cook them. Usually it is just a matter of replacing the dried-out moisture with boiling water.

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 ple.ntiful; 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 US 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 Refuge could be a major new US 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 tons of carbon, and burning the entire reserves could eventually raise world temperatures by 13~C. Among other horrors, this would result in the destruction of all rainforests and tile inching of all Arctic ice.

单选题There are fossil remains of dinosaurs In the rocky strata of every continent.

单选题We"ve been through some rough times together.

单选题A New Cause of Suffering A conference on obesity (肥胖症) was recently held in Vienna. Two thousand experts from more than fifty countries attended the conference. According to statistics, 1.2 billion people worldwide are overweight, and 250 million are too fat. Obesity is rapidly becoming a new cause of suffering. Professor Friedrich hopichler of Salzberg said: "we are living in the new age but with the metabolism (新陈代谢) of a stone-age man. I have just been to the United States. It is really terrible. A pizza (比萨饼) shop is appearing on every corner. We have been occupied by fast food and Coca-Cola-ization." Many of the experts stressed that obesity was a potential killer. Hopichler said: "Eighty percent of all diabetics (糖尿病人) are too fat, also fifty percent of all patients with high blood pressure and fifty percent with fatty tissue complaints. Ten percent more weight means thirteen percent more risk of heart disease. Reducing one"s weight by ten percent leads to thirteen percent lower blood pressure." Another expert Hermann Toplak said that the state health services should improve their financing of preventive programs. "The health insurance pays for surgery (such as reducing the size of the stomach) when the body-mass index (身体质量指数) is more than 40. That is equivalent to a weight of 116 kilograms for a height of 1.60 meters. One should start earlier." Toplak said that prevention should begin in school. "Child obesity has a close relation with the time which children spend in front of TV sets."