it was strange that he should have said that

题目

it was strange that he should have said that
我知道这是虚拟语气,但是虚拟语气不是should+动词原形吗,为什么这里是have done,如果是表示已经做过,那it's a pity that he should fail to grasp the chance when it arose.怎么解释,不也应该用should have failed吗

答案

首先should have done确实是表示已经做过,这里的should有惊讶的意思,意味着“竟然做过”

你说的it's a pity that he should fail to grasp the chance when it arose,如果没有when it arose,那么这句就应该是it's a pity that he should have failed to grasp the chance

BUT后面有个when it arose!

你从意思层面想想,机会来的时候竟然没有把握住,那么这个没有把握住是和机会来的时候是同一时刻,如果用have failed to grasp,那么意思变成了机会来“之前”竟然没有把握住