Whenever, however, Whatever, Whichever 分别是什么意思,并且用在什么句式中?

这些词我们分两组来记忆：
由副词+ever构成：whenever,wherever,however 引导让步状语从句时,他们意思分别是”不论何时“,"不论何地”,”无论如何“,并且可以分别转换成No matter when/no matter where/no matter how.
例如：wherever he goes,he takes his baby with him.=No matter where he goes,he take his baby.
由代词+ever构成：whatever,whichever,whoever（现在英语中不再用whomever做其宾格）这三个词既可以引导让步状语从句,分别表示”不论什么“,“无论哪个”,“无论是谁”；同时这三个词还可以引导名词性从句,此时不能转换.
Whatever happens,I will stand by you (让步状语 从句,此时whatever=No matter what)
Whoever get to the top of the mountain will be offer a prize.（whoever引导主语从句,此时不可转换)