误 Why did you come to fall into the river?
正 How did you come to fall into the river?
析 现代汉语的“为什么”,有时指“如何”“怎么样”。
为什么不去求老师帮忙呢?误 Why don't ask the teacher for help?
正 Why not ask the teacher for help?
析 Why not do...?是Why don't you/we do...?的省略形式,无主语时不用助动词do, not后直接加动词原形。
你有什么理由要休假呢?误 Is there any reason that you should have a holiday?
正 Is there any reason why you should have a holiday?
析 当名词reason作定语从句的先行词时,引导词只能用why。
