基数词1one2two3three4four5five6six7seven8eight9nine10ten11eleven12twelve13thirteen14fourteen15fifteen16sixteen17seventeen18eighteen19nineteen20twenty21twenty-one22twenty-two23twenty-three24twenty-four25twenty-five26twenty-six27twenty-seven28twenty-eight29twenty-nine30thirty31thirty-one32thirty-two33thirty-three34thirty-four35thirty-five36thirty-six37thirty-seven38thirty-eight39thirty-nine40forty41forty-one42forty-two43forty-three44forty-four45forty-five46forty-six47forty-seven48forty-eight49forty-nine50fifty51fifty-one52fifty-two53fifty-three54fifty-four55fifty-five56fifty-six57fifty-seven58fifty-eight59fifty-nine60sixty61sixty-one62sixty-two63sixty-three64sixty-four65sixty-five66sixty-six67sixty-seven68sixty-eight69sixty-nine70seventy71seventy-one72seventy-two73seventy-three74seventy-four75seventy-five76seventy-six77seventy-seven78seventy-eight79seventy-nine80eighty81eighty-one82eighty-two83eighty-three84eighty-four85eighty-five86eighty-six87eighty-seven88eighty-eight89eighty-nine90ninety91ninety-one92ninety-two93ninety-three94ninety-four95ninety-five96ninety-six97ninety-seven98ninety-eight99ninety-nine100ahundred序数词1、第一类:在括号里的是缩写形式,均在阿拉伯数字后面加上相应序数词的最后两个字母构成,以下各类与此相同。)first(1st)第一second(2nd)第二third(3rd)第三2、第二类:这一类序数词均在相应的基数词后面加上后缀-th构成。要注意其中fifth、eighth、ninth、twelth四个词的拼法。fourth(4th)第四fifth(5th)第五sixth(6th)第六seventh(7th)第七eighth(8th)第八ninth(9th)第九tenth(10th)第十eleventh(11th)第十一twelfth(12th)第十二thirteenth(13th)第十三fourteenth(14th)第十四fifteenth(15th)第十五sixteenth(16th)第十六seventeenth(17th)第十七eighteenth(18th)第十八nineteenth(19th)第十九3、第三类:这一类全是十位整数的序数词。它们的构成方法是:先将相应的十位整数的基数词词尾-ty中的y改成i,然后在加上后缀-eth。twentieth(20th)第二十thirtieth(30th)第三十fortieth(40th)第四十fiftieth(50th)第五十sixtieth(60th)第六十seventieth(70th)第七十eightieth(80th)第八十ninetieth(90th)第九十4、第四类:这类表示“第几十几”的序数词,十位数不变,仅把个位上的基数词变成序数词就行了。thirty-first(31th)第三十一sixty-second(62nd)第六十二eighty-seventh(87th)第八十七ninety-eighth(98th)第九十八