单选题What's the reason for the success of their trip?

单选题Where Did All the Ships Go? The Bermuda Triangle is one (51) the greatest mysteries of the sea. In this triangular area between Florida, Puerto Rico and Bermuda in Atlantic, ships and airplanes (52) to disappear more often than in (53) parts of the ocean. And they do so (54) leaving any sign of all accident or any dead bodies. It is (55) that Christopher Columbus was the first person to record strange happenings in the area. His compass stopped working, a flame came down from the sky, and a wave 100 to 200 feet high carried his ship about a mile away. The most famous disappearance in the Bermuda Triangle was the US Naval Air Flight 19. (56) December 5,1945,five bomber planes carrying 14 men, (57) on a training mission from the Florida coast. Later that day, all communications with Flight 19 were lost. They just disappeared without a trace. The next morning,242 planes and 19 ships took part in the largest air-sea search in history. But they found nothing. Some people blame the disappearances (58) supernatural forces. It is suggested the (59) ships and planes were either transported to other times and places, kidnapped by aliens (60) attacked by sea creatures. There are (61) natural explanations ,though. The US Navy says that the Bermuda triangle is one of two places on earth (62) a magnetic compass points towards true north (63) magnetic north. (64) planes and ships can lose their way if they don't make adjustments. The area also has changing weather and is known (65) its high waves. Storms can turn up suddenly and destroy a plane or ship. Fast currents could then sweep away any trace of an accident.

单选题{{B}}第二篇{{/B}} {{B}}Sleep Lets Brain File Memories{{/B}} To sleep. Perchance to file? Findings published online this week by the Proceedings of the National Academy of Sciences further support the theory that the brain organizes and stows memories formed during the day while the rest of the body is catching zzz's. Gyorgy Buzsaki of Rutgers University and his colleagues analyzed the brain waves of sleeping rats and mice. Specifically, they examined the electrical activity emanating from the somatosensory neocortex (an area that processes sensory information) and the hippocampus, which is a center for learning and memory. The scientists found that oscillations in brain waves from the two regions appear to be intertwined. So-called sleep spindles (bursts of activity from the neocortex) were followed tens of milliseconds later by beats in the hippocampus known as ripples. The team posits that this interplay between the two brain regions is a key step in memory consolidation. A second study, also published online this week, by the Proceedings of the National Academy of Sciences, links age-associated memory decline to high glucose levels. Previous research had shown that individuals with diabetes suffer from increased memory problems. In the new work, Antonio Convit of New York University School of Medicine and his collaborators studied 30 people whose average age was 69 to investigate whether sugar levels, which tend to increase with age, affect memory in healthy people as well. The scientists administered recall tests, brain scans and glucose tolerance tests, which measure how quickly sugar is absorbed from the blood by the body's tissues. Subjects with the poorest memory recollection, the team discovered, also displayed the poorest glucose tolerance. In addition, their brain scans showed more hippocampus shrinkage than those of subjects better able to absorb blood sugar. "Our study suggests that this impairment may contribute to the, memory deficits that occur as people age," Convit says. "And it raises the intriguing possibility that improving glucose tolerance could reverse some age-associated problems in cognition." Exercise and weight control can help keep glucose levels in check, so there may be one more reason to go to the gym.

单选题Both main parties are backing these proposals.A. supportingB. discussingC. suggestingD. making

单选题The hotel staff are friendly and courteous .

单选题We had trouble finding a pure water supply.

单选题{{B}}第二篇{{/B}} {{B}} A Fire near Waco{{/B}} Six years later, in an about-face, the Federal Bureau of Investigation(FBI) admits that federal agents fired tear gas canisters capable of causing a fire at the Branch Davidian compound near Waco, Texas in 1993. But the official said the firing came several hours before the structure burst into flames, killing 80 people including the Davidians' leader, David Koresh. "In looking into this, we've come across information that shows some canisters that can be deemed pyrotechnic in nature were fired—hours before the fire started,” the official said. “Devices were fired at the bunker, not at the main structure where the Davidians were camped out." The FBI maintains it did not start what turned to be a series of fiery bursts of flames that ended a 51-day standoff between branch members and the federal government. "This doesn't change the bottom line that David Koresh started the fire and the government did not," the official said. "It simple shows that devices that could probably be flammable were used in the early morning hours. " The law enforcement official said the canisters were fired not at the main structure where the Davidian members were camped out but at the nearby underground hunker. They bounced off the bunker's concrete roof and landed in an open field well, the official said. The canisters were fired at around 6 a. m., and the fire that destroyed the wooden compound started around noon, the official said. The official also added that other tear gas canisters used by agent that day were not flammable or potentially explosive. While Coulson denied the grenades played a role in starting the fire, his statement marked the first time that any U. S. government official has publicly contradicted the government's position that federal agents used nothing on the final day of the siege at Waco that could have sparked the fire that engulfed the compound. The cause of the fiery end is a major focus of an ongoing inquiry by the Texas Rangers into the Waco siege.

单选题The little girl grasped her mother"s arm as she crossed the street.

单选题What kind of planet elsewhere in the universe can support life?

单选题Many athletes oppose the new regulations on sports uniforms.

单选题We can utilize water for producing electric power.

单选题Why was the football match called off? A. held up B. put off C. ended D. cancelled

单选题Problems that Manufacturers Face Manufacturers who wish to export their goods to other countries 【51】 many practical problems. Firstly, there is the question of evaluating the market, and 【52】 where the product 【53】 well. This 【54】 examining rival products to see 【55】 these already fill the demand or not, and considering if the proposed selling price will be competitive. 【56】 is to find someone in the chosen market 【57】 will buy the product. The buyer could be a wholesaler, who will 【58】 sell the product to shops and stores, or someone with a retail outlet of 【59】 own. Finally, there''s 【60】 whole question of arranging the details of the deal, such as finance, transportation, storage. 【61】 a manufacturer knows the export market very well indeed, the best answer to all these problems is undoubtedly to find a good agent, who can make the whole project viable. An agent will provide information, introductions and contacts, and in return, he or she will get an 【62】 percentage form the manufacturer. When Paul Osman, the Sales Manager of Jayal Motors, which 【63】 mopeds, visited a city in an attempt to break into a new market, finding an agent was his first job. He was fortunate to be introduced to Adam Fortesque, a well established agent, who is 【64】 impressed by the Jayal mopeds to put his assistant, Eve Sorrell, on to the job of helping Paul in his proposed expansion into the export market. 【65】 , this attempt brings its own problems, and Paul has realized that Jayal Motors will have to adapt quickly if it is to become an expanding international company.

单选题Save Pandas With the Switzerland-based World Wildlife Fund (WWF), China is making a concerted and dedicated effort to save the endangered pandas. The results, officials here in Chengdu indicate, are mixed but encouraging. A clear disappointment is the failure to breed pandas in captivity, necessary if their decreasing numbers are to be replaced. Another failure has been the incapability to find a natural, readily available able food to replace the arrow bamboo. Despite these failures, success has come on two fronts. One achievement has been the physical rescue effort. Some pandas have been kept alive by salting (空投) the mountains with tons of cooked meat, which pandas will eat as a substitute for bamboo, and by the planting of new bamboo in isolated areas. Animals in some Sichuan areas have been rescued by local peasants and given emergency treatment by animal doctors. A second achievement is a massive fund-raising effort. Publicity about the pandas plight has resulted in a new $100,000 emergency allocation by the WWF and independent fund drives both in China and abroad. In spite of this support, there have been conflicts in the panda relief program. One important problem is the difficulty Peking is having balancing the recommendations of environmentalists with China"s ambitious goal of agricultural and industrial modernization. Wolong is but one example of this difficulty. This 494,000-acre preserve was declared a protected area in 1975. Yet 1,800 people, mostly Tibetans, still live in the preserve, logging trucks still roll down the narrow mountain roads, and blasting work still goes on at the site of a new 160,000-kilowatt hydroelectric plant just six miles away. This all means that the pandas" fight for survival will not be an easy one, even with the concerted effort of man. For in the end, even if they can survive the dangers of the wild, they must still contend with man himself.

单选题I was shocked when I saw the size of the telephone bill.

单选题Britain's Solo Sailor Ellen MacArthur started sailing when she was eight, going out on sailing trips with her aunt. She loved it so much that she saved her money for three years to buy her first small sailing boat. When she was 18, she sailed alone around Britain and won the "Young Sailor of the Year" award. But Ellen really became famous in 2001. Aged only 24, she was one of only two women who entered the Vendee Globe round the world solo race, which lasts 100 days. Despite many problems, she came second in the race out of 24 competitors and she was given a very warm welcome when she returned. Ambition and determination have always been a big part of Ellen's personality. When she was younger, she lived in a kind of hut for three years while she was trying to get sponsorship to compete in a transatlantic race. Then she took a one-way ticket to France, bought a tiny seven meter class mini yacht, slept under it while she was repairing it, and then she raced it 4,000 kilometers across the Atlantic in 1997, alone for 33 days. Ellen has had to learn many things, because sailing single-handed means that she has to be her own captain, electrician, sail maker, engineer, doctor, journalist, cameraman and cook. She also has to be very fit, and because of the dangers of sleeping for long periods of time she's in the middle of the ocean, she has trained herself to sleep for about 20 minutes at a time. And she needs courage. Once, In the middle of the ocean, she had to climb the mast of a boat to repair the sails at four o'clock in the morning, with 100kph winds blowing around her. It took her many hours to make the repairs. Ellen says, "I was exhausted when I came down. It's hard to describe how it feels to be up there. It's like trying to hold onto a big pole, which for me is just too big to get my altos around, with someone kicking you all the time and trying to shake you off." But in her diary, Ellen also describes moments which make it all worthwhile: "A beautiful sunrise started the day, with black clouds slowly lit by the bright yellow sun. I have a very strong feeling of pleasure, being out here on the ocean and having the chance to live this. I just feel lucky to be here./

单选题People have always been both fascinated by the spectacle of volcanic eruptions and terrified of their {{U}}power{{/U}}.

单选题He hasn"t the funds to carry out his design.

单选题Jesse and his boss are good friends.

单选题Fruits such as apples and oranges are very wholesome , and may be eaten at any time.