Question

虚拟语气 if You could have done other career What would it have been ? 为什么不是 if .. Had done 句

Answer 1

情态动词和实义动词、助动词一样，也有虚拟语气，它可以表示与现在或过去事实相反的非真实条件句，可以用于if条件从句，也可以用于主句。当表示与现在事实相反时，只把情态动词变成过去式（即时态往前退一格）即可，表示与过去事实相反时，情态动词要变成过去式，后面接助动词have加上过去分词。如：
If I hadn't told you, you could have been killed. （情态动词的虚拟语气用于主句）
Joyce would have been astonished if she could have heard his voice. （情态动词的虚拟语气用于if从句）
I couldn't have been angry with him if I had tried.
你给出的句子，是属于与过去事实相反的非真实条件句，这里用了情态动词can的虚拟语气，所以连接词if后面不能用过去完成时，而是要把情态动词can变成过去时的could，再后接have加过去分词的结构。希望我能帮助你解疑释惑。

Answer 2

是这个句型，虚拟语气。因为前面有could

追问

我知道是虚拟句，但是对过去的虚拟不是if it had done sth ....it Would have been 吗？谢谢！