As 和 like 在“像……一样”这个意思上很相似，口语里经常混用。此外，as 还有一个很常用的意思：

as 作为……

He works as a teacher.

他是一名老师。

He worked for a long time as a teacher in Africa.

他在非洲当了很长一段时间的老师。

X 不能说 work like a teacher X

① As your father, I'll help you as much as I can.

② Like your father, I'll help you as much as I can.

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① As your father, I'll help you as much as I can.

作为你的父亲，我会尽我所能帮助你。[说话人就是听的人的父亲]

② Like your father, I'll help you as much as I can. 

像你的父亲一样，我会尽我所能帮助你。[说话人并不是听话人的父亲，但希望像父亲一样]

as much as I can 尽我所能

as + 名词 作为 

like + 名词 像……一样，用一样的方式，类似于……