在肯定句中用 as...as...，在否定句中可以用 so...as...。

但是，如果是在疑问句中呢？可以用 so...as...吗？

【答】如果在疑问句中有not,可以用 so...as...,否则就不能。例如：Is he not as/so friendly as she is?他不像她那样友好吗？Is it as good as you expected? 它有你预期的那么好吗？(不能说：Is it so good as you expected?)

as...as 用于肯定句

I never went through a final exam that was as difficult as that one.

我从来没有碰到过像那次那么难的期末考试。

not so...as..用于否定句

There was no obvious reason why this could not be so good a film as the original.  

找不出明显的理由来解释为什么这部片子拍得不如原先的好。