独立主格为什么用BEING,There being no bus,we had to walk home.

题目

独立主格为什么用BEING,There being no bus,we had to walk home.
There being no chance to win ,we had to give it up .
为什么不用am is are was were?

答案

因为am is are was were是构成句子时的动词形式,而being是非谓语动词中的现在分词形式