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在EXCEL中，要将有数据且设置了格式的单元格恢复为普通空单元格，应先选定该单元，然后使用( )。
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Trillions of incredibly tiny diamonds, possibly formed by a dying star before the solar system was born 4.5 billion years ago, have been found by researchers (26) four meteorites. The powder-like diamonds could be among the oldest things in the (27) , said Roy Lewis, senior research associate at the University of Chicago. The diamonds may (28) clues about the chemistry of stars, and if scientists can determine how they formed, that could suggest better ways of manufacturing tiny diamonds for (29) purposes, he said. "It’s quite possible that nature is doing it more (30) than we’ve been doing it," he said. "So maybe we’ve got something to learn." The new find is (31) , said John Wood, staff scientist at the Harvard-Smithsonian Centre for Astrophysics. Although diamonds have been found before in meteorites, they were formed relatively recently (32) the shock of impact, he said in a telephone interview. But Wood said the new report made him "quite sure" the newly found diamonds are older than the sun. Lewis said researchers never expected to find diamonds when they started (33) a stone-like meteorite that had plunged into Mexican cornfield in 1969. They were studying an unusual carbon dust in the meteorite, and to purify the sample they went though several steps to dissolve other materials. They expected the sample to remain black through the purification, but to their surprise in the final step it turned (34) . Lewis said they believed the final stage had dissolved the carbon they wanted to study. But tests showed that the white residue was in fact made of carbon. Other tests found that it contained an unusual combination of forms of the gas xenon, (35) that it came from outside the solar system. Still another battery of tests (36) the residue as diamond dust, so fine that a row of 20,000 grains would extend about the (37) of a human hair. The researchers also found diamonds in three other meteorites, Lewis said. Tests showed all four meteorites were as old as the solar system, and that the embedded diamonds did not form within the meteorite (38) of collisions. So the diamonds must have (39) somewhere else before the meteorites formed, making them as old or older than the solar system. The diamonds may have formed in the upper atmosphere of a star in the late "red giant" stage, where the temperature and abundance of hydrogen could (40) diamonds to form as carbon gas condenses.
Trillions of incredibly tiny diamonds, possibly formed by a dying star before the solar system was born 4.5 billion years ago, have been found by researchers (26) four meteorites. The powder-like diamonds could be among the oldest things in the (27) , said Roy Lewis, senior research associate at the University of Chicago. The diamonds may (28) clues about the chemistry of stars, and if scientists can determine how they formed, that could suggest better ways of manufacturing tiny diamonds for (29) purposes, he said. "It’s quite possible that nature is doing it more (30) than we’ve been doing it," he said. "So maybe we’ve got something to learn." The new find is (31) , said John Wood, staff scientist at the Harvard-Smithsonian Centre for Astrophysics. Although diamonds have been found before in meteorites, they were formed relatively recently (32) the shock of impact, he said in a telephone interview. But Wood said the new report made him "quite sure" the newly found diamonds are older than the sun. Lewis said researchers never expected to find diamonds when they started (33) a stone-like meteorite that had plunged into Mexican cornfield in 1969. They were studying an unusual carbon dust in the meteorite, and to purify the sample they went though several steps to dissolve other materials. They expected the sample to remain black through the purification, but to their surprise in the final step it turned (34) . Lewis said they believed the final stage had dissolved the carbon they wanted to study. But tests showed that the white residue was in fact made of carbon. Other tests found that it contained an unusual combination of forms of the gas xenon, (35) that it came from outside the solar system. Still another battery of tests (36) the residue as diamond dust, so fine that a row of 20,000 grains would extend about the (37) of a human hair. The researchers also found diamonds in three other meteorites, Lewis said. Tests showed all four meteorites were as old as the solar system, and that the embedded diamonds did not form within the meteorite (38) of collisions. So the diamonds must have (39) somewhere else before the meteorites formed, making them as old or older than the solar system. The diamonds may have formed in the upper atmosphere of a star in the late "red giant" stage, where the temperature and abundance of hydrogen could (40) diamonds to form as carbon gas condenses.
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Last year, our nation’s capital passed the murder-a-day mark, and the number of homicides is now up some 50 percent from that level. More than half of these killings are drag-related. In 1988 New York City had its most violent year ever, with 1896 homicides. Many of these involved drugs. Such homicides are also a problem in Detroit, Baltimore, St. Louis, Los Angeles, Phoenix and scores of other cities where drug gangs war against one another and use violence to spread their deadly trade. In Bankhead Courts, and Atlanta housing project, drug-related crime has reached the point where mail carriers have had to depend on increased police patrols at delivery time. For years, we have attacked the supply side of the drug crisis, trying to choke off the flow of drugs into our country and stop the networks that distribute them. This strategy has failed miserably. Now it’s time to launch a whole new offensive. We must crack down on drag consumers. Last year, former First Lady Nancy Reagan had an emotional meeting with the parents of young woman who had died in a train crash that involved an engineer’s use of drugs. After that meeting, Mrs. Reagan said, "If you’re a casual drug user, you’re an accomplice to murder." Mary Jane Hatcher, widow of a New York City drug-enforcement agent killed in the drug wars, echoes that sentiment. "Even through the grief," she said after her husband’s death earlier this year, "I must ask, who really killed Everett Emerson from our society Look around. We middle-class suburban Americans, we casual users, we dabblers in drugs keep the market in drugs an ever-increasing one. Therefore, Everett Emerson Hatcher was killed by all of us. Nice people. All of you who hear me now and fit this description, all of you must accept the blame for the loss of this good, gentle man.\ Who should be blamed for the death of Everett Emerson Hatcher
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