___________, i would have phoned you.
问题描述：
___________, i would have phoned you.
A.if i knew it B.had i known itC.if i know it D.did i know it
为什么选B,要有理由.
答
虚拟语气,这是对过去的事进行推测,had i known it =if i had known it
选A的话,后面不应该是i would have phoned you ,应该是i would phone you
不懂再问