If I had V-ed, I would
结构︰Ifhad+过去分词，主词+would/should 等+原形动词+now/today
说明︰这是时态不一致时的假设句型，亦称混合假设条件句。即：if 子句若与过去事实相反，用过去完成式而主要子句若与现在事实相反，则用过去式助动词表示。此类主要子句句尾通常有表现在的时间副词，如 now，today 等。
If he had worked harder when young, he would be well off now.
如果他年轻时多努力一点，现在就能过得舒服些。
If I had been rich ten years ago, I could buy that house today.
如果十年前我有钱，今天我就能买下那栋房子了。
Had he told the truth, he wouldnt be punished now.
如果他当时肯说实话，现在就不会受罪了。
Had he followed the doctors advice, he might be alive now.
当时他要是听了医生的建议，现在可能还活着。