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Electric Backpack Backpacks 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 WoodsHole, 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 goggles, and other battery powered devices to get around and do their work. The backpack’s electricity-generating feature could dramatically reduce the amount of a wearer’s load now devoted to spare batteries, 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 down as the person walks. A gear mechanism converts vertical movements of 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 same time. 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 the street! According to Paragraph 4, what does Rome plan to do
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阅读下面短文，从短文后所给的[A]、[B]、[C]三个选项中选出能填入相应空白处的最佳选项。 Every Saturday, Mr. Brown went (Example: (0) ) the market to buy food and other things. He put (41) in a big basket. He was old and weak, so he always (42) a man to carry the basket home for him. But one Saturday, while he (43) home in front of the man with (44) , the man ran away (45) it. The next week, when Mr. Brown went to the market again , a friend of his said , "Look, (46) ! That man took away your food last week ! " Mr. Brown at once ran behind a shop, and stayed there (47) the man left the market. His friend was very (48) , "Why did you do that. he asked. "Well, "said Mr. Brown, "that man was carrying my basket when he left me a week ago. He will want me to pay him for (49) , and that (50) me more than a basket full of food."
Questions 47 to 56 are based on the following passage. Since we are social beings, the quality of our lives depends in large measure on our interpersonal relationships. One strength of the human condition is our tendency to give and receive support from one another under (47) circumstances. Social support consists of the exchange of resources among people (48) on their interpersonal ties. Those of us with strong support systems appear better able to cope with major life changes and daily hassles. People with strong social ties live longer and have better health than those without such ties. Studies over a (49) of illnesses from depression to heart disease, (50) that the presence of social support helps people fend off illnesses, and the (51) of such support makes poor health more likely. Social support cushions stress in a number ways. First, friends, relatives and co-workers may let us know that they (52) us. Our self-respect is strengthened when we feel accepted by others despite our faults and difficulties. Second, other people often provide us with informational support. They help us to define and understand our problems and find (53) to them. Third, we typically find social (54) supportive. Engaging in leisure-time activities with others helps us to meet our social needs while at the same time (55) us from our worries and troubles. Finally, other people may give us instrumental support, financial aid, material resources, and needed services that reduce stress by helping us (56) and cope with our problems.A) rangeB) valueC) concentratedD) solutionsE) absenceF) disappearanceG) revealH) resolveI) distractingJ) stressful K) protecting L) companionship M) ways N) based O)assess
What will the woman do
Born on July 31, 1965, in Gloucestershire, England, Joanne Kathleen Rowling grew up in rural communities in the southwestern part of that country. Rowling’s childhood experiences (67) her future literary creations. She explored the English countryside, visiting (68) and historical sites which inspired her (69) .Although she disliked science and mathematics courses, Rowling (70) in literature classes. She penned funny, fantastical tales to (71) her sister Diana and friends, (72) the Potter siblings whose name she later (73) for her wizardry novels. As a teenager, Rowling dreamed of becoming a (74) author whose books were sold in stores. She kept her ambitions a secret, (75) , because she feared criticism and discouragement from people who might declare that her writing was (76) Rowling gradually became more self-confident and was (77) Head Girl during her final year at school. (78) languages at Exeter University in order to be (79) as a bilingual secretary, Rowling graduated with a degree in French and Classics. This (80) knowledge aided her later clever (81) of characters in the Harry Potter books. Rowling then (82) to Manchester for other office positions. She wrote fiction for adult readers but did not (83) it for publication. She also often visited her (84) mother. It was during one of these train trips (85) Rowling began inventing characters and (86) .
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