I think they are interesting中的they为什么不用宾格?

问题描述:

I think they are interesting中的they为什么不用宾格?
再举几个相同的 例子

这句话里省掉了 that.原句是:
I think that they are interesting.
they 是宾语从句中的主语.
其他例子还有:
I hope (that) they'll come and visit me.
He believed (that) his girlfriend was mad at him.
.