(单选题)

______, I’d have told you.

A.If I would have known it

B.Had I known it

C.If I had have known it

D.Should I know it

参考答案：B

参考解析：

考查省略if，had提前的用法。句意：我要是知道的话，我就告诉你了。根据句意可知，此句应该用虚拟语气，而从主句I’d have told you中的时态可知，是虚拟语气中与过去事实相反的主句结构，非真实条件句的从句中谓语动词时态变化为“过去完成时had done”的形式，其中if可省略，had提到句首，故选B。

知识点：虚拟语气英语专业基础知识英语语法教师招聘-小学英语