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∑上面是100,下面是n等于1.后面是(n-1)等于多少------（填写最后的计算结果 ）求求你了! (N+2)!/(N+1)!等于多少? 1*2*(n-2)*(n-1) 等于多少?为什么? 选择:kangkang likes ＿＿＿A.most them B.most of them C.most of they 社会分工是指什么 Our teacher is-------a red sweater,A、puting on B、wearing 1.选择 The sweater ______our Chinese teacher is old.A.on B.with c.in d .under 选择 The sweater _______ our Chinese teacher is old.A with B on C in D at 选择 The sweater ______our Chinese teacher is old. A.on B.with c.in d .under 丑小鸭变白天鹅的实例急用! 17.She’s seriously ill.Please _____ the doctor at once.A.send to B.send about C.send for D.send out mother is seriously ill .we must （）a doctor at once . all of boys are young pioneers 改错 All of us are Young Pioneers.同义句______ of us ______ a Young Pioneers. 英语it's a matter of life and 我妈妈都会说英语Happiness in marriage is entirely a matter of choice ,not chance, determines human destiny 是什么意思 It is a matter of. 英语翻译Desting is not a matter of chance;It is a matter of choica.It is not a thing to de waited for;It is a thing to de a chieved. 英语翻译东方神起的love after love的歌词中要有哪段是谁唱的 英语翻译]New York,I Love You But you're bringing me down[00:12.12]New York,I Love You But you're bringing me down[00:20.68]Like a rat in a cage Pulling minimum wage[00:31.70]New York,I Love You But you're bringing me down[00:41.70]New York,you're People will laugh at you if you wear such a modern dress.改成被动语态 you should believe that native speakers will not laugh at you.一句话中只能有一个动词,其他的都是非谓语动词.包括动词不定式,动名词,现在分词.那这句话中不是有should 和laugh两个动词? A s( )is a funny show .The people in it do or say things that make TV w( )laugh.求各位：前面给出一个首字母,括号里填什么?谢谢! You dial love has closed down什么意思《翻译成中文》 THEY were very ____when they___each other that year.选项：A: young; got to know B: old; had know这是一中实验班的题目,请高手来做! They were ______(砍）a tall tree down when I saw them.这个题,谁若知道就告诉我, 首字母填空They were _____(讨论) a Math problem when I saw them初二英语首字母填空1.They were _____(讨论) a Math problem when I saw them.2.The plane_____(碰撞)into the mountains. Maybe because I took them home when they were very ______A.old B.tall C.young D.healthy 英语翻译不对? 提问：It's easy_(be)wise after the event请说明原因 it is easy (to be)wise after the event为什么用be?be不是be动词 代表的是am is are的嘛 要么就是被动be是原形 那么 am is are算是他的什么？