（一）基數(shù)詞 在英語中表示數(shù)目的詞稱為基數(shù)詞。
1.基數(shù)詞的構成
（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 先說“幾十”，再說“幾”，中間加連字符。
23→twenty-three,34→thirty-four,45→forty—five,56→fifty-six,67→sixty-seven,78→seventy-eight,89→eighty-nine,91→ninety-one
（3）101—999先說“幾百”，再加and,再加末兩位數(shù)或末位數(shù)；
586→five hundred and eighty-six,803→eight hundred and three
（4）l,000以上,先從右往左數(shù)，每三位數(shù)加一個“,”,第一個“,”前為thousand.第二個“,”前為
million,第三個“,”前為billion（美式）或thousand ,million（英式）,然后一節(jié)一節(jié)地表示。
1,001→one thousand and one
9,785→nine thousand, seven hundred and eighty-five
18,423→eighteen thousand,four hundred and twenty-three
6,260,309→six million two hundred and sixty thousand three hundred and nine
750,000,000,000→seven hundred and fifty, billion（美式） seven hundred and fifty thousand million（英式）
2.基數(shù)詞的用法
（1）作主語
eg.Four Of them come from Paris.
（2）作賓語
eg.一 How many books would you like？
一I would like two.
（3）作表語
eg.Seven minus two is five.
（4）作定語
eg.There are three people in my family·
（5）作同位語
eg. You two will go swimming with us.
（6）表具體數(shù)字時,hundred,thousand,million用單數(shù)。
eg. There are six hundred students in our grade.
（7）表不確定的數(shù)字時,數(shù)詞用復數(shù)。若帶名詞，再加of hundreds of（數(shù)百,成百上千的）,thousands of（數(shù)干,成千上萬的）,millions of（數(shù)百萬）
eg,They arrived in two sand threes.他們三三兩兩地來了。
（8）表示“…十”的數(shù)詞的復數(shù)可以表示人的歲數(shù)或年代。
eg. He is in his early thirties.他有三十來歲（31—34歲）：
This took place in the 1930s.這事發(fā)生在二十世紀三十年代；
（9）表示時刻
eg.I watch CCTV News at seven o’clock every evening.
本文來自：逍遙右腦記憶 http://simonabridal.com/zhongkao/1327322.html
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