1. What 和whatever都可以引导名词性从句（包括主语从句，宾语从句，表语从句，同位语从句）， 但意义略有不同。What相当于the thing that， 而whatever相当于anything that。 例句： 1) What you need is a good meal. (主语从句) The thing that you need is a good meal.(先行词为the thing 的定语从句) 2） I’ll give her what she needs. (宾语从句) （意为：我会给她她需要的东西。） I’ll give her the thing that she needs. (先行词为the thing 的定语从句) 3）I’ll give her whatever she needs. (宾语从句) （我会给她任何她需要的东西。） I’ll give her anything that she needs. (先行词为the thing 的定语从句) 比较2） 和3）组例句体会what 和whatever在语义上的不同。 2. Whatever 可以引导让步状语从句，what不可以。 1) Whatever she needs, I’ll give it to her. 2) You’ll have our support, whatever you decide. Whatever引导的状语从句可以转换为：no matter what引导的句子 3) No matter what she needs, I’ll give it to her. 4) You’ll have our support, no matter what you decide. 5) I ’ve decided to leave tomorrow, no matter what (happens). 不管发生什么情况，我已决定明天走。 6) In our company, every body is well taken care of, no matter what his position (is). 在我们公司，每个人都得到很好的照顾，不管他地位如何。 3. Who， whom 和whoever以及whomever的区别（语义不同，可以引导的从句不同，在从句中的作用不同） 1）Who 可以做名词性从句连接词，也可以做定语从句关系代词，在从句中做主语或替代主语。（口语中也可以用who替代whom） 2）Whom 可以做名词性从句连接词，也可以做定语从句关系代词，在从句中做宾语或替代宾语。（不可以用whom 代替who） 3）Whoever 和whomever可以做名词性从句连接词，也可以做定语从句关系代词，和who 和whom的区别主要在意思不同，Whoever 和whomever表示“无论谁”。 4）Whoever 和whomever可以引导状语从句，转换成no matter who 或者no matter whom 的句子。（同whatever一样） 比较以下一组句子： The man who called yesterday wants to buy the house. (定语从句， 先行词在从句中做主语) The man whom called yesterday wants to buy the house. （×） Can you tell me to whom you are writing? (介词后的宾语从句) Can you tell me who you are writing to? （口语中也可以用who替代whom）（宾从） He was free to marry whomever he chose. (宾语从句) He was free to marry her, no matter whom he chose. (状语从句) Whoever says that is a liar. （说这话的人是一个骗子）（主语从句） Anyone who says that is a liar. (说这话的那个人是一个骗子)（定从） No matter who says that, he is a liar. (状语从句) 本文来源：https://www.wddqw.com/doc/cf1521945af5f61fb7360b4c2e3f5727a4e92402.html