英语序数词的变化规则

表示顺序的数词叫序数词，是由基数词变化而来的。•1one-----first•2two------second•3three----third•4其余的序数词是由基数词后加-th变化而来。几个特殊变化的序数词•1five----fifth•2twelve----twelfth•3eight----eighth•4nine----ninth整十数的序数词是把整十数基数词的词尾ty改为tie再加-th•1twenty----twentieth•2thirty----thirtieth•3forty----fortieth•4fifty-----fiftieth•5你能写出sixtyseventyeightyninety的序数词吗？•1.Sixty----sixtieth•2.seventy---seventieth•3.eighty----eightieth•4,ninety----ninetieth几十几的序数词，十位数不变，个位数变成序数词，中间用连字符“-”连接。•1.twenty-one21twenty-first21st•2.thirty-two32thirty-second32nd•3.ninety-nine99ninety-ninth99th•4.请写出66834855的序数词。方法：在阿拉伯数字的后面加上序数词的最后两个字母。例如：first1sttwenty–first21stsecond2ndtwenty–second22ndthird3rdsixty–third63rdfifth5theighty–fifth85thninth9thninety-ninth99th一、二、三，单独记；八去t，九减e；f要把ve替；整十基数变序数，ty改为tie；要是遇到两位数，十位基数个位序，一二三后th加上去。一二三单独记，one→first，two→second，three→third这三个词变化特殊，要单独记；八去t，九减e后再加-th，eight→eighth，nine→ninth；五、十二把ve换成f再加-th，five→fifth，twelve→twelfth；整十先把词尾ty改为tie再加-th，twenty→twentieththirty→thirtieth；两位数时则十位数用基数词，个位数用序数词，twenty-first。