[家教老师]

同级比较 "as…as…"

 1. as…as 的基本意思为“与……一样”，第一个as副词，第二个as可用作介词(后接名词或代词)或连词(后接从句)，中间通常接形容词或副词(用原级)，但如果有数量或程度，可用“as much+不可数名词+as”和“as many+可数名词复数+as”：
    My brother is as tall as my father.
    He plays basketball as well as Mike.
    You made as many mistakes as I did in the exams.
   
    中间用形容词时，有时候也可以接一个带有 a/ an 的名词。
    He wants to be as good a basketball player as Yaoming.

    在否定句中，第一个 as 也可换成 so：
    I am not as (so) tall as my sister. 我不如我妹妹高。
 2. 在非正式场合(尤其是美国英语中)，有时可以省略第一个as。如：
    he prefers to marry a girl rich as himself. 他想娶一个像他一样富有的女孩。

    若意思明确，有时也可省略第二个as及其后的相关词语。如：
    The things in that shop will be cheaper, but not as good.
     那家商店的东西会便宜些，但质量没那么好。

 3. as...as..结构根据情况也可用使用以下修饰语：(not) nearly, almost, just, nothing like,    exactly, not quite, half, one-ten, twice, three times, 30 per cent等，但这些修饰语必须放在第   一个as之前，而不能放在其后。如：

   He doesn't study half as well as his sister. 他的学习不及他姐姐的一半好。
   This pair of shoes is twice as expensive as that. 这双鞋比那双贵一倍。

  Plus:
    我们也用 the same ...as ...表示“与....一样”，但 the same 后必须用名词. 如:
   She is as old as me. 她与我同龄。
   She is the same age as me.