It is strange that she should have failed to see her own shortcomings.这句话里为什么不是用S不是说it is adj that...(should) do 为何不是用should fail?

It is strange that she should have failed to see her own shortcomings.这句话里为什么不是用S不是说it is adj that...(should) do 为何不是用should fail?
It is strange that she should have failed to see her own shortcomings.这句话里为什么不是用S
不是说it is adj that...(should) do 为何不是用should fail?

It is strange that she should have failed to see her own shortcomings.这句话里为什么不是用S不是说it is adj that...(should) do 为何不是用should fail?
should有两种用法,一种是一般时态,另一种是完成时态,这里强调的是过去,所以用完成时表示,表示fail已经做过了.
老师祝你学习进步!
望采纳,多谢!^_^

你的语法没错，should have， have是原形，而不是说fail应该是动词原形。

这里用的是虚拟语气。不是所有的相容词和动词都有虚拟语气。

这句话中用的是have done的原型，表示对过去动作的的惊叹。