when,while,so that,so...that,such...that,wether应该怎么区分?

一 when ①当.时
while ①当.时②虽然③然而
注意：①在表示“当.时”while后面必须加延（持）续性动词,而when则无特殊要求
eg：Tom broke into the room while Ben was sleeping.
eg:Tom broke into the room when Ben closed the window.
② 如果时间状语从句的动词为延（持）续性动词 ,引领词必须用while,绝不可以用 when （英语中规定的）
eg：Tom broke into the room while Ben was sleeping.（不能用when,这很关键）
二 so 和such的区别在于：so 后面加形容词或副词
such 后面加名词
eg：Tom is so humorous(幽默的) that every one likes him.
eg:Tom is such a humorous boy that every one likes him.
注意：So.that...可用于倒装句,so that 引领结果状语从句,解释为“以致于”
eg：So complex （复杂的）was the problem that no one of us could solve the problem.
eg：I got up early this morning so that I could get to school on time.
三whether 表疑问,解释为“是否”
eg：Tom didn't know whether he could pass the exam.
注意：当从句中出现or 时,必须用whether ,不能用if
eg:Tom didn't know whether he could pass the exam or not.(此时不能用if来替代whether)