if用于虚拟语气,主句用would,could,should,might+动词原形,这4个词...答:If father hadn't sent me, I shouldn't have come.另:had+过去分词,用于一切人称和数 If we had left earlier,we wouldn't have missed the train.(美国英语的结果主句,不管什么人称,都常用would)以上should,would均为情态助动词.即本身无实意,只是构成时态语态作用.以下为情态动词用于虚拟语气的...