reason在定语从句中的用法

reason在定语从句中的用法

例句1：The reason why he could not go there was that his grades were too low.

The reason why...is that... 这是特定句型, why引导定语从句,is后的用词为that,一般不用because.又如：

例句2:The reason why she did it is that she wouldn’t let her parents feel disappointed.她做那件事是因为她不想让父母失望。

该句中的why引导一个定语从句，而that引导表语从句。

(1) 句中that引导的表语从句说明主语reason的具体内容

注意以下两种结构：

①The reason is / was that …当主语是reason / cause时，一般不能用

because或why引导表语从句，以免造成语意重复。

The reason why/for which(也可以省去) he was late was that he got up late.

他迟到的原因是他起床晚了。

②当主语是This / That时，可以由because / why引导表语从句。

He got up late. That was why he was late for class.

He was late for class. That was because He got up late.

(2)why在句中是关系副词，引导定语从句，修饰先行词reason，同时它在定语从句中作状语，此时why = for which，但要注意：关系词在定语从句中做主语或宾语时，要用关系代词that或which。

The reason why/for which(也可以省去) he was late was that he got up late.

他迟到的原因是他起床晚了。

The reason that/which/(也可以省去) he gave you was reasonable.

他给你的理由是合理的。

【练习】

-- I drove to Zhuhai for the air show last week.

-- Is that ____ you had a few days off?

A. why

B. when

C. what

D. where

变式①Is this the reason ____ at the meeting for his carelessness in his work?

A. he explained

B. what he explained

C. how he explained

D. why he explained

变式②The reason ____he failed to pass the exam was ____ he never studied hard.

A. why what

B. because that

C. why that

D. why because

变式③Is this the reason _____ he was punished? Which of the following is wrong?

A. why

B. for which

C. 不填

D. that