六年级英语上册常用基数词与序数词素材人教PEP版常用基数词与序数词1.one—first 2.two—second 3.three—third 4.four—fourth 5.five—fifth 6.six—sixth 7.seven—seventh 8.eight—eighth 9.nine—ninth 10.ten—tenth 11.eleven—eleventh 12.twelve—twelfth 13.thirteen—thirteenth 14.fourteen—fourteenth 15.fifteen—fifteenth 16.sixteen—sixteenth 17.seventeen—seventeenth 18.eighteen—eighteenth 19.nineteen—nineteenth 20.twenty—twentieth 21.twenty-one—twenty-first 22.twenty-two—twenty-second 23.twenty-three—twenty-third 24.twenty-four—twenty-fourth 25.twenty-five—twenty-fifth 26.twenty-six—twenty-sixth 27.twenty-seven—twenty-seventh 28.twenty-eight—twenty-eighth 29.twenty-nine—twenty-ninth 30.thir1ty—thirtieth 31.thirty-one—thirty-first1。