有一读者问：高中英语第一册有这样一句话：
He heard a noise, as if someone was breathing.
有人认为 as if someone was breathing 是状语从句，也有人认为是定语从句，修饰 noise，不知您的看法如何？
这个 as if 从句可以有两种分析方法。它既可看作状语从句，亦可看作定语从句。如看作状语从句，它就相当于 as if he heard someone breathing； 如看作定语从句，它就相当于 which was as if someone was breathing。
