Question

---______the accident happened?--- It's said to happen on his way to work.

A．Do you know it is where that
B．Where is it that do you know
C．Do you know where it is that
D．Where do you know it is that
答案选D。从回答来看我们排除AC，从BD中选，但是强调句的特殊疑问句结构是特殊疑问词+be+it+that+句子，只有在宾语从句或者表语从句中，特殊疑问词引导的的从句才是正常语序，而题目是问句，从语序上来说，D不对，为什么不选B呢？加入插入语会影响整个句子的语序吗？

Answer 1

你好。
先完善你的错句：-- Where do you know it was that the accident happened?
-- It's said to have happened on his way to work.
答案是：Where do you know it was that

1 强调句如果修饰过去的事情，结构是(比如说)：where was it that + 句子（谓语动词是一般过去时）/ where it was that + 句子（谓语动词是一般过去时）.

2 在这样的结构中，It's said to -- - - - ， 如果主语补足语部分的动作 比is said 先发生，这个主语补足语部分必须是to have happened,不是to happen.

Answer 2

去掉问号的的语序是：It is where that the accident happened.可以看出强调句强调的地点状语。因为do you know 不是插入语，其实是一个宾语从句的主语和谓语。

you know 后面应该接一个宾语从句，而这个宾语从句就是It is where that the accident happened这个强调句。

应该是Do you know it is where that the accident happened。
但是根据答语可知，要问的是地点，所以where提到前面
成了Where do you know it is that the accident happened？

所以这是一个宾语从句套强调句的结构

所以啊，就满足你说的“强调句的特殊疑问句结构是特殊疑问词+be+it+that+句子，只有在宾语从句或者表语从句中，特殊疑问词引导的的从句才是正常语序”

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