_______the meeting,he would have attended.
A.If he knew B.If he hadn't known C.Had he known D.If he didn't know
C正确.当条件状语从句虚拟过去时，句型是：If 主语＋had done sth,主语＋would have done sth.这时间，从句可省略为：Had +主语＋done sth,主句不变．你的问题中，因为主句谓语动词形式是would have done,那从句谓语动词一定是：had done.B选项虽然时态对，但意义不对，该是肯定才对．而C项正式省略倒装形式．
答：看到后面的“would have+过去分词”了吗?这是个虚拟条件句子，主句用“would have+过去分词” ，if从句谓语动词形式就用“had+过去分词”，...详情>>
答：B 被动语态，be found to do. A中的made与found均为过去分词，冲突！详情>>
问：hArd work 和hArd--working有什么区别
答：一个是名词 一个是形容词撒详情>>
