代词选择

问题描述:

代词选择
Though no one knew ___,it would be the last day he would stay in Paris.He would return to China the next day.
A it B/ C that D.this
为什么不是C ,

it用于某些动词后,无实义或词义模糊,构成习语
I have it.Let the sheep cross the bridge first
而CD不可以代替后面整个句子的