It was clear from the survey that teenages have similar hopes.

问题描述:

It was clear from the survey that teenages have similar hopes.
这是一个什么从句,为什么

这是一个强调句结构,It is(was)+被强调的部分+that(who)+原句其它部分
句意是:显然,在调查中青少年都有类似的希望.