The private automobile has long played an important 　　1　　 in the United States．In fact, it has become a necessary and important part of the American way of life．In 1986, sixty-nine percent of American families owned at least one car, and thirty-eight percent had more 　　2　　 one．By giving workers rapid transportation, the automobile has freed them from having to live near their place of work．This has encouraged the 　　3　　(grow)of the cities, but it has also led 　　4　　 traffic problems．

　　Family life has been affected in various ways, The car helps to keep families together 　　5　　 it is used for picnics, outings．However, when teenage children have the use of the car, their parents can't keep 　　6　　 eye on them．There is a great danger if the driver has been drinking alcohol(酒精)or 　　7　　(take)drugs, or showing off by speeding or breaking down traffic laws．Mothers of victims(罹难者)of such accidents have formed an 　　8　　(organize)called MADD．These women want to prevent further tragedies(悲剧)．They have worked to encourage the government to limit the youngest drinking age, Students have formed a 　　9　　(similarity)organization, SADD, and are spreading the same message among their friends．

　　For many Americans the automobile is a 　　10　　(necessary)．But for some, it is also a mark of social position and for young people, a sign of becoming an adult．Altogether, cars mean very much to Americans．

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