http://www.wjhsqzx.com/sites/personal/pdq/Article_Show.asp?ArticleID=53这个网面是专门讲这的。简略的如下
一、基本用法
as ... as
用于比较句型,中间插入的是形容词或副词的原级。意思是"达到与什么相同的程度"。如：He is as strong as a horse. 他力大如牛。
二、习惯用法
1. as soon as
意思是"一......就......",引导一个时间状语从句。如：I'll call you as soon as I finish my homework. 我一完成我的作业,就给你打电话。
2. as long as
意思是"长达......之久；只要......"。如：She has searched the information about dinosaurs on the Internet as long as three hours. 她在因特网上搜索有关恐龙的信息已经长达三个小时。
3. as much as
意思是"高达......；与......一样多"。是用来表达极其多的语气。如：Some of the stones weigh as much as fifteen tons.有些石头重达15吨。