All that"s important is that you are doing your best and moving in the right direction 为什么要填ALL

问题描述:

All that"s important is that you are doing your best and moving in the right direction 为什么要填ALL
答案说All作that"s important 定语从句的先行词(为什么要用ALL作先行词,that"s important 不能作先行词,怎样才为先行词?).All that相当于what引导的名词性从句(为什么说下定语从句,一会又说是名词性从句,难不成这句话可理解为名词性从句,).让我感到很乱,难以理解,括号里的就是我的疑问,或者有更好的解释也可以,我基础比较薄弱,最好明了一些,

all 是先行词,that's important 是定语从句,对其修饰限制.
在语法上,all that =what,所以,由定语从句知识可以跨越到名词性从句,即:what is important is that .
不必担心,背下来,见多了,就见怪不怪了.