as词性多,词义广,用法灵活,现将其用法归纳如下:
I. as作副词, 表示程度, 意为“同样地”。“as…as…”,表示“和/与……一样”,是同级比较,其中第一个as是副词;否定句中常用“not so…as…”,表示“和/与……不一样”。如:
Jack is as tall as his father.杰克和他的父亲一样高。
He doesn’t speak English so/ as fluently as you.
他的英语说得不如你流利。

II. as作介词。
①如,像
They got united as one man.
他们团结得像一个人一样。
She spoke of me as her dearest friend。
她谈起我犹如我是她最亲密的朋友。
②充当,作为
As a writer, he was famous.作为作家,他是很有名的。
English is spoken as the first language by most people in Australia.
在澳大利亚,大多数人把英语作为第一语言。