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知识点总结 数词分为基数词和序数词两种; (一)基数词在英语中表示数目的词称为基数词。 1.基数词的构成 (1)1-20 one,two,three,four,five,six,seven,eight,nine,ten,eleven,twelve,thirteen,fourteen,fifteen, sixteen,seventeen,eighteen,nineteen,twenty (2)21-99 先说“几十”，再说“几”，中间加连字符。 23→twenty-three,34→thirty-four, (3)101—999先说“几百”，再加and,再加末两位数或末位数; 586→five hundred and eighty-six,803→eight hundred and three (4)l,000以上,先从右往左数，每三位数加一个“,”,第一个“,”前为thousand.第二个“,”前为million,第三个“,”前为billion,然后一节一节地表示。 9,785→nine thousand, seven hundred and eighty-five 6,260,309→six million two hundred and sixty thousand three hundred and nine 750,000,000,000→seven hundred and fifty, billion 2.基数词的用法 (1)表示数量 Eg. 一 How many books would you like? 一I would like two. (2)表示号码 eg.My phone number is 6887789. (3)表示时间 eg.I watch CCTV News at seven o’clock every evening. (4)表示“…十”的数词的复数可以表示人的岁数或年代。 eg. He is in his early thirties.他有三十来岁(31—34岁)： This took place in the 1930s.这事发生在二十世纪三十年代; (5)表具体数字时,hundred,thousand,million用单数。 eg. There are six hundred students in our grade. (6)表不确定的数字时,数词用复数。若带名词，再加of ，hundreds of(数百,成百上千 的),thousands of(数干,成千上万的),millions of(数百万) eg 。 Hundreds of old people died of cold last winter. (二)序数词在英语中表示顺序、次序的词称为序数词。 1.序数词的构成 (1)一般在基数词后加th, eg.four→fourth,thirteen→thirteenth,多位数把个位变序数词。 基数词变为序数词的规则(口诀)： 基变序，有规律，词尾加上 th;一、二、三特殊记，结尾t、d、d。 八减t，九减e，f要把ve替。ty把y改为i，记得th前有个e。 (责任编辑：admin) |