题干

某物体运动的位移图象如图所示,以下说法正确的是(  )

A:物体在0~2s做匀变速直线运动

B:物体在0~2s的加速度为3m/s2

C:物体在2~6s的平均速度为3m/

D:物体在2~6s的路程为12m

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D

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阅读理解

    Many people have tried to simplify (简化) the spelling of English words. Unlike other languages, English sometimes spells the same sounds in very different ways. For example, there is “light” but “white”, “loan” but “phone”, and there are at least seven different ways of pronouncing “ough”, “though”, “through”, “bough”, “cough”, “enough”, “ought” and “thorough”.

    The American President Theodore Roosevelt almost succeeded in simplifying English spelling. In 1906, one of the richest men in the United States of America, Andrew Carnegie, started the Simplified Spelling Board whose plan was to make the spelling of words nearer to the way they sound. For example, the word “though” would be spelt “though” and “through” would become “thru”. Other people on the board were Melvil Dewey, the head of the New York libraries, and Professor Brander Matthews of Columbia University. They explained their idea to President Roosevelt who thought that it was indeed logical (合理的).He immediately instructed the government printer to use simplified spelling in all government letters.

    But people did not like the change — even if it made life easier— and the new, simpler spelling was not popular. More importantly, when the American politicians discussed the plan, they did not like it either. Because Roosevelt did not want to have any problems with the politicians, he changed his mind and told the printer to go back to the old way of spelling.

    Since then no one in any government has dared to simplify English spelling. However, people do simplify some words, mainly in advertisements. For example, we often see “tonite” instead of “tonight” and “thru” instead of “through”.