as...as的用法
as...as意為"和……一樣",表示同級的比較.使用時要注意第一個as為副詞,第二個as為連詞.其基本結構為：as+ adj./ adv.+as.例如：
(1)This film is as interesting as that one.這部電影和那部電影一樣有趣.
(2)Your pen writes as smoothly as mine.你的鋼筆書寫起來和我的一樣流暢.
其否定式為not as/so +adj./ adv.+as.例如：
This dictionary is not as/so useful as you think.這本字典不如你想象的那樣有用.
若有修飾成分,如twice,three times,half,a quarter等,則須置于第一個as之前.例如：
Your bag is twice as expensive as mine.你的袋子比我的貴一倍.