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第二篇Explorer of the Extreme Deep Oceans cover more than two-thirds of our planet. Yet, just a small fraction of the underwater world has been explored. Now, Scientists at the Woods Hole Oceanographic Institution (WHOI) in Massachusetts are building an underwater vehicle hat will carry explorers as deep as 6,500 meters (21,320 feet). The new machine, known as a manned submersible or human-operated vehicle (HOV), will replace another one named Alvin which has an amazing record of discovery, playing a key role in various important and famous undersea expeditions. Alvin has been operating for 40 years but can go down only 4,500 meters (14,784 feet). It’s about time for an upgrade ,WHOI researchers say. Alvin was launched in 1964. Since then, Alvin has worked between 200 and 250 days a year, says Daniel Fornari, a marine geologist and director Of the Deep Ocean Exploration Institute at WHOI. During its lifetime, Alvin has carried some 12,000 people on a total of more than 3,000 dives. A newer, better versions of Alvin is bound to reveal even more surprises about a world that is still full of mysteries, Fornari says. It might also make the job of exploration a little easier. "We take so much for granted on land. " Fomari says. "We can walk around and see with our eyes how big things are. We can see colors, special arrangements. " Size-wise, the new HOV will be similar to Alvin. It’ll be about 37 feet long. The setting area inside will be a small sphere, about 8 feet wide, like Alvin. It’ll carry a pilot and two passengers. It will be just as maneuverable. In most other ways, it will give passengers more opportunities to enjoy the view, for one thing. Alvin has only three windows, the new vehicle will have five, with more overlap so that the passengers and the pilot can see the same thing. Alvin can go up and down at a rate of 30 meters every second, and its maximum speed is 2 knots (about 2.3 miles per hour), while the new vehicle will be able to ascend and descend at 44 meters per second. It’ll reach speeds of 3 knots, or 3.5 miles per hour. What is Alvin
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试论科教兴国战略的内涵及其意义。
下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。Computer and School Education There was a time when parents who wanted an educational present for their children would buy a typewriter, a globe or an encyclopedia set. Now those (51) seem hopelessly old-fashioned; this Christmas, there were a lot of personal computers under the tree. (52) that computers are the key to success, parents are also financially insisting that children (53) taught to use them in school—as early as possible. The problem for schools is that when it (54) computers, parents don’t always know best. Many schools are (55) parental impatience and are purchasing hardware without sound educational planning so they can say, "OK, we’ve moved into the computer age. " Teachers found themselves caught in the middle of the problem—between parent pressure and (56) educational decisions. Educators do not even agree (57) how computers should be used. (58) money is going for computerized educational materials (59) research has shown can be taught just as well with pencil and paper. (60) those who believe that all children should have access to computers, warn of potential dangers to the very young. The temptation remains strong largely because young children (61) so well to computers. First graders have been seen willing to work for two hours on math skills. Some have an attention span of 20 minutes. (62) school can afford to go into computing, and creates yet another problem: a division between the haves and have-nots. Very (63) parents are agitating (64) computer instruction in poor school districts, (65) there may be barely enough money to pay the reading teacher.
下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。Computer and School Education There was a time when parents who wanted an educational present for their children would buy a typewriter, a globe or an encyclopedia set. Now those (51) seem hopelessly old-fashioned; this Christmas, there were a lot of personal computers under the tree. (52) that computers are the key to success, parents are also financially insisting that children (53) taught to use them in school—as early as possible. The problem for schools is that when it (54) computers, parents don’t always know best. Many schools are (55) parental impatience and are purchasing hardware without sound educational planning so they can say, "OK, we’ve moved into the computer age. " Teachers found themselves caught in the middle of the problem—between parent pressure and (56) educational decisions. Educators do not even agree (57) how computers should be used. (58) money is going for computerized educational materials (59) research has shown can be taught just as well with pencil and paper. (60) those who believe that all children should have access to computers, warn of potential dangers to the very young. The temptation remains strong largely because young children (61) so well to computers. First graders have been seen willing to work for two hours on math skills. Some have an attention span of 20 minutes. (62) school can afford to go into computing, and creates yet another problem: a division between the haves and have-nots. Very (63) parents are agitating (64) computer instruction in poor school districts, (65) there may be barely enough money to pay the reading teacher.
下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。Computer and School Education There was a time when parents who wanted an educational present for their children would buy a typewriter, a globe or an encyclopedia set. Now those (51) seem hopelessly old-fashioned; this Christmas, there were a lot of personal computers under the tree. (52) that computers are the key to success, parents are also financially insisting that children (53) taught to use them in school—as early as possible. The problem for schools is that when it (54) computers, parents don’t always know best. Many schools are (55) parental impatience and are purchasing hardware without sound educational planning so they can say, "OK, we’ve moved into the computer age. " Teachers found themselves caught in the middle of the problem—between parent pressure and (56) educational decisions. Educators do not even agree (57) how computers should be used. (58) money is going for computerized educational materials (59) research has shown can be taught just as well with pencil and paper. (60) those who believe that all children should have access to computers, warn of potential dangers to the very young. The temptation remains strong largely because young children (61) so well to computers. First graders have been seen willing to work for two hours on math skills. Some have an attention span of 20 minutes. (62) school can afford to go into computing, and creates yet another problem: a division between the haves and have-nots. Very (63) parents are agitating (64) computer instruction in poor school districts, (65) there may be barely enough money to pay the reading teacher.
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