把 A变成AN 如何说1.a become an 2.a go to an.3.a change an .这三种说法都对吗

把 A变成AN 如何说1.a become an 2.a go to an.3.a change an .这三种说法都对吗 How to becom a happy boy A man becom learned by asking questions Don'e think too much of yourself . 在什么情况下单词前面要把a变成an 照样子把五个元音字母变成各种单词 例:A...+N...AN...+D...AND...+H...HAND 1.A 2.E 3.I 4.O 5.U 为什么half an hour later 中an不变成a 知道递推公式如何求通项公式 例如 An=2A(n-1)-1 如何变成通项公式 如何区分a和an 英语翻译There is an umbrella support for a long time,the rain stopped but also would not take; There is a bunch of flowers has smelled for a long time,wither would not lose; there is a hope to the permanent friendship,even if the black hair becom 已知数列{an}满足a1=2,a(n+1)-an=a(n+1）*an,则a31=?你是怎么想到要除以a(n+1)an的?a(n+1)-an=a(n+1）*an怎么变成1/a(n+1)-1/an=-1？好像没说重点哦？ 如何把do you have a car?变成肯定句?(不是肯定的回答) 如何把do you have a car?变成肯定句?(不是肯定的回答) 如何把I bought a present for yoy变成同义句 照样子把五个元音字母变成各种单词 例:A...+N...AN...+D...AND...+H...HANDE+H? 英语小白来问问题a nurse took him to the bedside of an old man可以把bedside of an old man变成old man's bedside吗? 改复数a,an要不要变成some获any I had a eat an apple.怎么变成一般疑问句 如何判断单词前的冠词用a还是an?把要用an的全部音标告诉我,