(1). 形容词或副词+as+主语+连系动词be或实义动词。例如：

　　Rich as he is, he never spends a cent on clothes. 虽然他很富有，但他从不花一分钱在衣服上。

　　Much as I admire his courage, I don't think he acted wisely. 我虽然佩服他的勇气，但我认为他这样做是不聪明的。

　　(2). 名词+as+主语+连系动词be (注意句首的名词不带冠词)。例如：

　　Child as he is, he knows a lot. 尽管他是个孩子，但懂很多事情。

　　Boy as he was, he was chosen king. 尽管他还是个孩子，但却被立为国王。

　　(3). 实义动词+as+主语+助动词[如果没有助动词，则要加上一个do(does或did)]。例如：

　　Try as he may, he never succeeds. 尽管他很努力，但总是不成功。

　　Change your mind as you will, you will gain no additional support. 即使你改变主意，你也不会得到另外的支持。

　　4. 引导方式状语从句，意为"如"，"像"，"按照……的方式"。如:

　　I want you to tell my friend your very interesting experience exactly as you have told it to me. 我想让你像给我讲述的那样，给我的朋友讲一讲你那段极其有趣的经历。

　　Remember, you must do everything as I do. 记住，你必须按照我做的那样做一切。

　　注意：like在非正式语体中可以有与as相同的用法。如：

　　I can't sing like I used to.我不能像以前那样唱歌了。

　　He writes just like his brother did when he was young. 他现在写文章正像他哥哥年轻时写文章一样。

　　5. 引导比较状语从句,用于"as...as...或 not so/ as...as..."中,前一个as是副词,后一个as是连词，意为"如(不如)…一样"。如:

　　(1). You hate her as much as I (=as I hate her).

　　(2). I don't speak English so/ as well as he does.

　　注意：句中连词as后面的代词实际是省略了与主句相同的部分，即例(1)可以写成You hate her as much as I hate her. 如果很明显就能看出所省略的部分，意义不会含糊不清时，在口语中也可以用代词的宾格形式。例：At your age you can't expect to play football as well as me (= as I do).但例(1)就不能改I为me，改后意思就变为：You hate her as much as you hate me. 你恨她像恨我一样深;而原句的意思为：你恨她像我恨她一样深。

　　三、作代词

　　as作关系代词的用法

　　关系代词as引导定语从句时，既可以单独使用，也可以与其他词连用，其用法要比that和 which更为复杂。

　　1. as引导定语从句与其他词连用

　　(1). 用于the same...as结构中

　　This is the same watch as I have lost. 这块手表跟我丢失的那块一样。

　　(2). 用于such...as结构中

　　I don't like such novels as you recommend. 我不喜欢你推荐的那些小说。

　　(3). 用于"so +adj. + a/an + n. (单数) + as "结构中

　　I am not so strong a man as I was. 我已经没有从前那么强壮了。

　　2. as单独引导定语从句

　　as单独引导定语从句时，先行词可以是一个词，也可以是一个句子或短语。例如：

　　(1) She is late, as is often the case. 她迟到了，这是经常的事。(先行词是整个主句)

　　(2) To shut your eyes to facts, as many of you do, is foolish. 对事实视而不见--你们好多人都是如此的愚蠢。(先行词是不定式短语)

　　注意1：(1). 当as引导的定语从句位于具有否定意义的主句之前时，as从句所修饰的范围是整个主句的内容，也就是说，把否定意义也包括在内。例如：

　　As has been said above, grammar is not a set of dead rules. 正如前面所说，语法不是一套死条文。

　　(2). 当as引导的定语从句位于具有否定意义的主句之后时，as从句所修饰的范围不包括否定意义。例如：

　　Spiders are not insects, as many people think. = Spiders are not insects. But many people think they are. 许多人认为蜘蛛是昆虫，但蜘蛛并不是昆虫。

　　(3). 当as引导的定语从句位于具有否定意义的主句中间时，as从句所修饰的范围也不包括否定意义。例如：

　　She did not, as her friend had feared, open the case. 她没有打开盒子，而她的朋友就是怕她当面打开盒子。

　　注意2: 当修饰句子的非限制性定语从句位于句尾时，as可以用which来替代。例如：