It was at the gate where I told him the news.是什么从句?是主语从句吗?

这是where引导的定语从句
关键是你对it的理解,这应该是一个有语境的提,单纯这句话it可以理解为地点
如果是个单选,你把题干发出来我再给你解释
It was at the gate where I told him the news that ...
如果是这样的语境,省略了后面的that从句,那么it是强调句结构的it无实际意义,where仍为定语从句
It was at the gate that I told him the news.
强调句有一个特征,就是你把it...that去掉仍然是一个完整的句子
I told him the news at the gate .
但是如果是主语从句,照你说的理解
That I told him the news was at the gate
这个句子就讲不通了

是强调句，强调“the gate” 不是主语从句

应该是强调句 强调地点状语at the gate 把it was where 一省 就变成了at the gate i told him the news.和一般强调句 it is...that...的结构差不多

这是一句强调式的定语从句，引导词是where，用来修辞 gate ，强调的是地点