怎么知道什么时候用哪个词引导让步状语从句while,although,though,despite,in spite of,as有时候despite不能而in spite of 能；有时候有while,就不选despite.求大神讲解下着6个词什么时候用,

怎么知道什么时候用哪个词引导让步状语从句while,although,though,despite,in spite of,as有时候despite不能而in spite of 能；有时候有while,就不选despite.求大神讲解下着6个词什么时候用,
怎么知道什么时候用哪个词引导让步状语从句
while,although,though,despite,in spite of,as
有时候despite不能而in spite of 能；有时候有while,就不选despite.
求大神讲解下着6个词什么时候用,

怎么知道什么时候用哪个词引导让步状语从句while,although,though,despite,in spite of,as有时候despite不能而in spite of 能；有时候有while,就不选despite.求大神讲解下着6个词什么时候用,
（1）though,although表示“虽然,纵然”之意.
　　这两个连词意思大致相同,在一般情况下可以互换使用.在口语中,though较常使用,although比though正式,二者都可与yet,still或never,the less连用,但不能与but连用.例如：
　　Although/Though he was exhausted,(still) he kept on working.虽然他已经精疲力竭了,但仍然继续工作.
　　Although/Though he is very old,(yet) he is quite strong.他虽然年纪大了,身体还很健壮.
　　值得注意的是,although引导的让步状语从句位于主句之前的情况较多,though引导的让步状语从句可位于主句之前或主句之后.例如：
　　She passed the examination though she had not studied very hard.她虽然不用功学习,考试却及格了.
用though/although,as 引导让步状语从句时,句中不能用but表示转折语气.
　　不能说：Though he looks weak,but he is healthy.
　　而要说：Though he looks weak,he is healthy.
　　或者说：He looks weak,but he is healthy.
　　我自己认为让步就是存在一定条件下的说法.
（2）as,though表示“虽然……但是”,“纵使……”之意.
　　as引导的让步状语从句必须以部分倒装的形式出现,被倒装的部分可以是表语、状语或动词原形,though也可用于这样的结构中,但although不可以这样用.例如：
　　Object as you may,I’ll go.(=Though/Although you may object,I’ll go.) 纵使你反对,我也要去.
　　Hard as/ though he works,he makes little progress.(=Though he works hard,he makes little progress.)尽管他学习很努力,但几乎没取得什么进步.
　　Child as/though he was,he knew what was the right thing to do.（=Though he was a child,he knew what was the right thing to do.）虽然他是一个孩子,但他知道该做什么.
　　Fast as you read,you can’t finish the book so soon.纵然你读得快,你也不能这么快读完这本书.
as 引导让步状语从句的用法
　　引导让步状语从句时,as意为“虽然,尽管”,通常从句要倒装,倒装的方法是将从句的表语或状语放在as之前,而用though引导让步状语从句时句字则不必倒装（口语中也可倒装）.
　　e.g.Heavily as it was raining outside,they started out very early.
　　Young as he is,he knows a lot=Though he is young 或Young though he is,he….
　　他虽然年轻,但懂得很多.(though 也有这种用法,可以替换as,但although没有这种用法)
　　注意,名词提句首时,不加冠词：
　　e.g：teacher as he is ,he likes Chinese very much(teacher 前不加a或the）.
　　though还可以用作副词,放在句末.如：
　　It was hard work;; I enjoyed it,though=It was hard work,but I enjoyed it.那工作很苦,但是我喜欢干.
（3）even if,even though 表示“即使……”,“纵使……”之意,含有一种假设.
　　这两个复合连词的意思基本相同.它们常互换使用,但意义有细微差别.even if引导的让步从句含有强烈的假定性,可用来表示与事实相反的假设,但不能用来描述已经发生的事实.而even though引导让步状语从句时,是以从句的内容为先决条件的,即说话人肯定了从句的事实,表示已经发生了的事.例如：
　　We’ll make a trip even if/though the weather is bad.即使天气不好,我们也要作一次旅行.
　　Even if he is poor,she loves him.(=He may be poor,yet she loves him.)即使他很穷,但她还是爱他.
　　Even though he is poor,she loves him.(=He is poor,yet she loves him.)尽管他很穷,但她还是爱他.