同位语从句（Appositive Clause）

同位语从句指的是在主从复合句中充当同位语的句子。

同位语和同位语从句：

当两个词或词组在一个句子中具有相同的语法地位而且描述相同的人或事物时，我们称它们为同位语。

Mr. Eric, our new team leader, is very kind.

同理，当两个指同一人或事物的句子成分放在同等位置时，若其中一个句子成分是用于说明或解释另一个句子成分的，那么用于起说明或解释作用的句子成分就叫做另一成分的同位语从句。

The news that our team has won the match is true.

同位语从句的连词

1、由连词that，whether引导的同位语从句，if不可以引导同位语从句。

There is no doubt that I will always stay with you.

The idea that you can do this work well without thinking is quite wrong.

We'll discuss the problem whether the sports meeting will be held on time.

The question whether we should call in a specialist was answered by the family doctor.

注意：在suggestion, advice, request, order等意为“建议；命令；要求”的名词后，同位语从句中的谓语动词通常用“should+动词原形”的虚拟语气结构，句中的should可以省略。

There was a suggestion that Brown should be dropped from the team.

The general gave the order that the soldiers should cross the river at once.

This is our only request that this problem be settled as soon as possible.

Our teacher gave us some advice how we (should) use the computer.

2、由连接代词what,who,whom,whose引导的同位语从句。

I have no idea what size shoes she wears.

The question who will take his place is still not clear.

I have no idea whom they are talking about.

I don't know the question which pen is mine.

3、连接副词when,where,how,why引导的同位语从句。

I have no idea when he will come back.

We haven't settled the question where we are going to spend our summer vacation.

He had no idea why she left.

I don't know the question where the concert will be held.

4、间隔同位语从句。

同位语从句通常是跟在它解释或说明的名词后，但有些情况下，由于句子结构的原因，同位语从句不紧跟在名词后，而被其他的词隔开，如：

A warm thought suddenly came to me that I might use the pocket money to buy some flowers for my mother's birthday.

说明：从句太长，为避免句子失去平衡，变为间隔同位语从句。

The rumour spread that a new school would be built here.

The order soon came that all citizens should evacuate the village.

The thought came to him that maybe the enemy had fled the city.

同位语从句的语序

同位语从句的语序用陈述语序

There is some doubt whether will he come.（X）

There is some doubt whether he will come. (√)

We are not investigating the question whether he is trustworthy. (√)

We are not investigating the question whether is he trustworthy.（X）

同位语从句的时态

同位语从句的时态不受主句时态影响和限制。

I know the reason why he was unhappy just now.

I have already knew the reason yesterday why he came late.

I am looking for the reason why he came late.

I will know the reason why he came late.