[虚拟语气用法及动词形式.doc

用法及动词形式 　　1、表示与现在事实相反的情况： 　　从句：If 主语+过去时(Be动词用were) 　　主句：主语+should/would/could/might+do 　　eg：　 　　1．If I were you,I would take an umbrella. 　　如果我是你，我会带把伞。（事实：我不可能是你） 　　2．If I knew his telephone number,I would tell you. 　　如果我知道他的电话号码，我就会告诉你。（事实：不知道） 　　3．If there were no air or water,there would be no living things on the earth. 　　如果没有水和空气，地球上就不会有生物。(事实：地球上既有空气也有水) 　　4．If I had any money with me,I could lend you some. 　　如果我带钱了，我就会借给你些。（事实：没有带钱） 　　5．If he studied harder,he might pass the exam. 　　如果他再努力些，就能通过考试了。（事实：没有努力） 　　6．she looked at me as if I had been a stranger. 　　她看我的样子好像我是一个陌生人。（事实：我并非陌生人）　 　　2、表示与过去事实相反的情况 　　从句：If 主语+had+done 　　主句：主语+should/would/could/might+have done　 　　eg： 　　1． If I had got there earlier,I should/could have met her. 如果我早到那儿，我就会见到她。 　　（事实：去晚了） 　　2．If he had taken my advice,he would not have made such a mistake. 如果他听我的劝告的话，就不会犯这样的错误了。 　　（事实：没有听我的话） 　　3、表示对将来情况的主观推测 　　从句：①if+主语+were to do 主句：①主语+should/would/could/might+do 　　②if+主语+did/were ②主语+should/would/could/might+do　 　　③if+主语+should+do ③主语+should/would/could/might+do　 　　eg： 　　1．If he should come here tomorrow,I would talk to him. 　　如果他明天来这儿的话，我就跟他谈谈。（事实：来的可能性很小） 　　2．If there were a heavy snow next Sunday,we would not go skating. 　　如果下周日下大雪，我们就不能去滑冰了。（事实：下雪可能性很小） 　　3．If she were to be here next Monday,I would tell her about the matter. 　　如果她下周一来这儿的话，我就会告诉她这件事的始末。（事实：来的可能性很小） 　　4、 有时，虚拟条件句中，结果主句和条件从句的谓语动作若不是同时发生时，虚拟语气的形式应作相应的调整。这种条件句叫错综条件句。 　　①从句的动作与过去事实相反，而主句的动作与现在或现在正在发生的事实不符。 　　eg： 　　If I had worked hard at school,I would be an engineer,too. 　　如果我在学校学习刻苦的话，我现在也会成为一个工程师了 　　If they had informed us,we would not come here now. 　　如果他们通知过我们的话，我们现在就不会来这里了。 　　②从句的动作与现在事实相反，而主句的动作与过去事实不符。 　　如： 　　If he were free today,we would have sent him to Beijing. 　　如果他今天有空的话，我们会已经派他去北京了。 　　If he knew her,he would have greeted her. 　　要是他认识她的话，他肯定会去问候她了。 　　5、 当虚拟条件句的谓语动词含有were,should,had时，if可以省略，这时条件从句要用倒装语序，即把were,should,had等词置于句首，这种多用于书面语。eg： 　　Should he agre