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,45→forty—five,56→fifty-six,67→sixty-seven,78→seventy-eight,89→eighty-nine,91→ninety-one
(3)—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(美式)或thousand ,million(英式),然后一节一节地表示。
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)
