第1个回答 2009-06-29
英语过去式出现在 一般过去时,I was late for school that day.
与现在事实相反的虚拟语气:If I were you, I would have been rich.
过去分词出现在: 现在完成时: I have finished my homework.
过去完成时:when I came home, my mother had cleaned my room.
与现在事实相反跟过去事实相反的虚拟语气
也用于被动语态:my room was cleaned by my mother.