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单选题The meaning is still Uobscure/U.
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单选题After the president made an official announcement, she expressed her personal opinion.
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单选题He {{U}}demolished{{/U}} my argument in minutes. A. supported B. disproved C. disputed D. accepted
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单选题Electric Backpack Backpacks (背包) are convenient. They can hold your books, your lunch, and a change of clothes, leaving your hands free to do other things. Someday, if you don't mind carrying a heavy load, your backpacks might also power your MP3 player, keep your cell phone running, and maybe even light your way home. Lawrence C. Rome and his colleagues from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in Woods Hole, Mass. , have invented a backpack that makes electricity from energy produced while its wearer walks. In military actions, search-and-rescue operations, and scientific field studies, people rely increasingly on cell phones, global positioning system (GPS) receivers, night-vision (夜视镜) goggles (护目镜), another battery powered devices to get around and do their work. The backpack's electricity-generating feature could dramatically reduce the amount o a wearer's load now devoted to spare batteries (备用电池), report Rome and his colleagues in the Sept. 9 Science . The backpack's electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer's back, and the whole pack moves up and clown as the person walks. Agear mechanism converts vertical movements o the pack to rotary motions of an electrical generator, producing up to 7.4 watts. Unexpectedly, tests showed that wearers of the new backpack alter their gaits in response to the pack's oscillations, so that they carry loads more comfortably and with less effort than they do ordinary backpacks. Because of that surprising advantage, Rome plans to commercialize both electric and non-electric versions of the backpack. The backpack could be especially useful for soldiers, scientists, mountaineers, and emergency workers who typically carry heavy backpacks. For the rest of us,power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the sametime. Electricity-generating packs aren't on the market yet, but if you do get one eventually, just make sure to look both ways before crossing thestreet !
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单选题The curious look from the strangers around her made her feel uneasy .
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单选题{{B}}第三篇{{/B}} In the 1950s, the pioneers of artificial intelligence (AI) predicted that, by the end of this century, computers would be conversing with us at work and robots would be performing our housework. But as useful as computers are, they' re nowhere close to achieving anything remotely resembling these early aspirations for humanlike behavior. Never mind something as complex as conversation: the most powerful computers struggle to reliably recognize the shape of an object, the most elementary of tasks for a tenmonth-old kid. A growing group of AI researchers think they know where the field went wrong. The problem, the scientists say, is that AI has been trying to separate the highest, most abstract levels of thought, like language and mathematics, and to duplicate them with logical, step-by-step programs. A new movement in AI, on the other hand, takes a closer look at the more roundabout way in which nature came up with intelligence. Many of these researchers study evolution and natural adaptation instead of formal logic and conventional computer programs. Rather than digital computers and transistors, some want to work with brain cells and proteins. The results of these early efforts are as promising as they are peculiar, and the new nature-based AI movement is slowly but surely moving to the forefront of the field. Imitating the brain' s neural (神经) network is a huge step in the right direction, says computer scientist and biophysicist Michael Conrad, but is still misses an important aspect of natural intelligence. "People tend to treat the brain as if it were made up of color-coded transistors," he explains, "but it's not simply a clever network of switches. There are lots of important things going on inside the brain cells themselves." Specifically, Conrad believes that many of the brain's capabilities stem from the pattern-recognition proficiency of the individual molecules that make up each brain cell. The best way to build an artificially intelligent device, he claims, would be to build it around the same sort of molecular skills. Right now, the notion that conventional computers and software are fundamentally incapable of matching the processes that take place in the brain remains controversial. But if it proves true, then the efforts of Conrad and his fellow A1 rebels could turn out to be the only game in town.
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单选题The economy continued to{{U}} exhibit{{/U}} signs of decline in September.
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单选题After entering the living room, he {{U}}removed{{/U}} his scarf and gloves.
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单选题They are endeavoring to change society as a whole.
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单选题Five minutes left, the outcome of the match was still in doubt.
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单选题You startled me when you shouted.
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单选题His kidney was given to his daughter so as to save her.
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单选题She was close to success.
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单选题{{B}}第二篇{{/B}} The Iceman On a September day in 1991.two Germans were climbing the mountains betwe.en Austria and Italy. High up on a mountain pass,they found the body of a man lying on the ice.At that height(10,499 feet, or 3,200 meters),the ice is usually permanent,but 1991 had been an especially warm year.The mountain ice had melted more than usual and so the body had come to the surface. It was lying face downward.The skeleton(骨架)was in perfect condition,except for a wound in the head.There was still skin on the bones and the remains of some clothes.The hands were still holding the wooden handle of an ax and on the feet there were very simple leather and cloth boots.Nearby was a pair of gloves made of tree bark(树皮)and a holder for arrows. Who was this man?How and when had he died?Everybody had a different answer to these questions.Some people thought that it was from this century,perhaps the body of a soldier who died in World War I,since several soldiers had already been found in the area.A Swiss woman believed it might be her father who had died in those mountains twenty years before and whose body had never been found.The scientists who rushed to look at the body thought it was probably much older,maybe even a thousand years old. With modern dating techniques,the scientists soon learned that the Iceman was about 5,300 years old.Born in about 3300 B.C.,he lived during the Bronze Age in Europe.At first scientists thought he was probably a hunter who had died from an accident in the high mountains.More recent evidence,how ever,tells a different story.A new kind of X-ray shows all arrowhead still stuck in his shoulder.It left only a tiny hole in his skin,but it caused internal damage and bleeding.He almost certainly died from this wound,and not from the wound on the back of his head.This means that he was probably in some kind of a battle.It may have been part of a larger war,or he may have been fighting bandits.He may even have been a bandit himself. By studying his clothes and tools,scientists have already learned a great deal from the Iceman about the times he lived in.We may never know the full story of how he died,but he has given us important clues to the history of those distant times.
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单选题The young man is too Ubashful/U to speak to strangers.
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单选题When the city was burned in 1814, he Urescued/U many official papers from the town hall.
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单选题We had only a vague description of the attacker.
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单选题He was rather vague about the reasons why he never finished school.A. brightB. unclearC. generalD. bad
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单选题The girl is gazing at herself in the mirror. A.smiling B.laughing C.shouting D.staring
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单选题 How to Dress Properly Being less than perfectly well-dressed in a business setting can result in a feeling of profound discomfort that may well require therapy to dispel. And the sad truth is that "clothing mismatches" on the job can ruin the day of the person who is wearing the inappropriate attire (着装), and the people with whom he or she comes in contact. Offices vary when it comes to dress codes. Some businesses have very high standards for their employees and set strict guidelines for office attire, while others maintain a more relaxed attitude. However, it is always important to remember that no matter what your company's attitude is regarding what you wear, you are working in a business environment and you should dress accordingly. Certain items may be more appropriate for evening wear than for a business meeting. Just as shorts and a T-shirt are better suited for the beach than for an office environment, our attire should reflect both your environment and your position. A senior vice president has a different image to maintain than that of a secretary or sales assistant. Like it or not, you will be judged by your personal appearance. This is never more apparent than on "dress-down days", when what you wear can say more about you than any business suit ever could. In fact, people will pay more attention to what you wear on dress-down days than on "business professional" days. Thus, when dressing in "business casual" clothes, try to put some flair into your wardrobe choices, recognizing that the "real" definition of business casual is to dress just one notch (等级) down from what you would normally wear on business-professional attire days. Remember, there are boundaries between your career and your social life. You should dress one way for play and another way when you mean business. Always ask yourself where you are going and how other people will be dressed when you get there. Is the final destination the opera, the beach, or the office? Dress accordingly and you will discover the truth in the axiom (公理) that clothes make the man and the woman. When in doubt, always err on the side of dressing slightly more conservatively than the situation demands.
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