1至15的基数加起来等于30

1:one—first2:two—second3:three—third4:four-fourth5:five—fifth6:six—sixth7:seven—seventh8:eight—eight

1.[wʌn]2.[tu:]3.[θri:]4.[fɔ:]5.[faiv]6.[siks]7.[ˈsevn]8.[eit]9.[nain]10.[ten]11.[i

1.有.它用来表示“其余的几个”.例如：Amongthefiveforeignvisitors,twospeakEnglish,theotherthreespeakGerman.在五位外宾中,两位说英

这个证明不难的,不过无限集的基数确实是个有意思的东西,比如偶数（2,4,6...2n)是正整数（1,2,3,...n)的一个真子集然而通过：2←→1,4←→2,6←→3,.,2n←→n,.它们之间建立

28293745412201927353644311101826344243219172533414948781624324037476141523313038465132122

序数词firstsecondthirdfourthfifthsixthseventheighthninthtentheleventhtwevlfththirteenthfourteenthfiftee

2\x099\x0947\x095\x0936\x091\x098

1：基数词：one序数词：first缩写：1st再答：2：基数词：two序数词：second缩写：2nd再答：3：threethird3rd再答：4：fourfourth4th再答：5：fivefif

你们老师这是抽那门子的疯,等下再答：序数词firstsecondthirdfourthfifthsixthseventheighthninthtentheleventhtwevlfththirteen

(1+174)×174÷2=15225再问：公式是什么？再答：n(n+1)/2

基数词：1one2two3three4four5five6six7seven8eight9nine10ten11eleven12twelve13thirteen14fourteen15fifteen1

基数词序数词基数词序数词基数词序数词onefirsteleveneleventhtwenty-onetwenty-firsttwosecondtwelvetwelfthtwenty-twotwenty

12345678910111213141516先这么排,把1和16,4和13,6和11,7和10调换就可以了对奇数排和九宫图都是有规律的,有时间一起研究一下吧

1:one—first2:two—second3:three—third4:four-fourth5:five—fifth6:six—sixth7:seven—seventh8:eight—eight

再答：上面那个

1one-first2two-second3three-third4four-fourth5five-fifth6six-sixth7seven-seventh8eight-eighth9nine-n

是13和17吧.30以内的质数：2,3,5,7,11,13,17,19,23,29,31.

1.one2.two3.three4.four5.five6.six7.seven8.eight9.nine10.ten11.elven12.twelve13.thirteen14.fourteen1

一，基数词！如何记英语100以内的基数词和序数词学习写数和记数是学习语言的开端。小学生在开始发蒙读书的时候，要从笔画和“一二三”学起；初学英语的人，也要从“ABCD”和“一二三”学起。学生常常会在一开

:one—first2:two—second3:three—third4:four-fourth5:five—fifth6:six—sixth7:seven—seventh8:eight—eighth