Nobody could have predicted the outcome.请问为什么要用could have predicted?

题目

Nobody could have predicted the outcome.请问为什么要用could have predicted?

答案

could have done 这是一个虚拟语气,表示'本可以做...".如：
We could have walked home.我们本可以回家的.
She could have predicted the outcome.她本可以预测到结果的.
你的句子就是这句话的否定式.