能否请老师帮忙详细总结一下：
1.that和what作为名词性从句引导词有什么区别。
2.whatever和whoever引导名词性从句和状语从句有什么区别。
1 that引导的名词性从句为陈述分句，即该从句原本是个陈述句。比如，I know that you are a student.
what则因为其本身可以是疑问词、感叹词和融合型关系词，所以what可以引导三种名词性从句：
1）名词性疑问分句：I don't know what he is trying to say.
2）名词性感叹分句：You can't believe what a stupid boy he is.
3）名词性关系分句：What he said is a lie.
2 whatever和whoever 既能够引导名词性从句，也可以引导让步状语从句。无论引导哪种从句，whatever和whoever都是要在从句中做成分的。不同在于主句中是不是缺少名词性成分。假如whatever/whoever引导的从句在主句中做了名词性成分如主语、宾语或表语，则这个从句就是名词性从句。假如主句的主语、宾语、表语齐全，不缺名词性成分，则whatever/whoever引导的就是让步状语从句。比如：
Whoever said that was lying. Whoever said that占据了was lying的主语的地方，所以这是名词性从句作主语。
Whoever said that, I won't believe him. 主句主谓宾齐全，whoever引导让步状语从句。
whatever的状况你一个人类推。
