求教一个英语的问题.There is no need to do 和There is no need dong 有区别不?要怎么用?打错了 是There is no need doing

求教一个英语的问题.There is no need to do 和There is no need dong 有区别不?要怎么用?打错了 是There is no need doing 一个包含英语的数学问题There is a duck in front of two ducks.There is a duck between two ducks.There is a duck behind two ducks.How many ducks are there?问：There are ________ 英语问题求教 求教一个基本的电磁学问题. 求教一个高数的问题 求教一句英语句子的语法What significance is there in gaining the world if it means losing yourself 解决一个英语小语法问题is there any book here?说这里的there be充当谓语那么可以is there having any book here?现在进行时 英语填空.This box is very light because there is n in it.there is后面可以填什么?n开头的如题 英语问题Is there a book on the table?Yes ,there is .Is the book red 带There weve there is there was 的英语句子 求教一个解极限的问题,当n趋近于无穷时,（2的n次方加上3的n次方）分之（2的n次方加上3的n+1次方）的极限? 求教一个有关数列的问题a(1)=4,a(n+1)=2a(n)-2n²+2n,求｛a(n)｝的通项公式.注：（）里的数代表项数,急, 求教英语,这句话的表达习惯有什么问题么?The room is not only big but also good. 如题 求教这句话在英语的表达习惯和用法上有错误嘛? 求教一道级数问题判断级数(1-无穷)n^2/e^(n^(1/2))的收敛性 英语问题：is there any book available 还是is there any books available?single or plural? 好简单英语问题(这个题目我用了N次了...)1 Let'e take tom___example.He sets a good example___us___working hard.for to by as for for2 In that case,there is nothing you can do___答案OTHER 这里的ORHER是什么意思 举多一个同样 线性代数问题求教：设A,B都是n阶方阵,如果AB=O,则A,B行列式的值是都为0还是只有一个为0? 求教英语填空There is _______ ,forks and plates on it.A)knivesB)a knifeC)some knife