问一个句子中that从句的成分It's high time that we left this shop.that从句作什么成分

问题描述:

问一个句子中that从句的成分
It's high time that we left this shop.
that从句作什么成分

It's high time that 要用虚拟语气(所以用过去时left)
早就应该离开商店了。

主语

that we left this shop.