大眼睛鱼儿
1、l would/should/could/might主句谓语中的should主要用于第一人称后；would表示结果还表示过去经常常常做某事，might表示可能性，could表示能力、允许或可能性。比较：If you tried again ，you would succeed. 要是你再试一试，你就会成功的。 (would表结果)If you tried again， you might succeed. 要是你再试一试，你可能会成功的。 (might表可能)If you tried again ，you could succeed. 要是你再试一试，你就能成功了。(could表能力)2、错综时间虚拟条件句 即条件从句与主句所指时间不一致，如从句指过去，而主句即指的是现在或将来，此时应根据具体的语境情况，结合上面提到的三种基本类型对时态作相应的调整：If it had rained last night, the ground would be wet now. 要是昨晚下过雨的话，现在地面就会是湿的。You would be much better now if you had taken my advice. 假若你当时听我的话，你现在就会好多了。3、If虚拟条件句的否定（含蓄条件句） 常考两个句型：If it weren’t for…和If it hadn’t been for…，其意为“若不是(有)” “要不是”。如：If it weren’t for water, no plant could grow. 要是没有水植物就无法生长。If it hadn’t been for your assistance ，we wouldn’t have succeeded.=But for your assistance ，we wouldn’t have succeeded.=Without your assistance ，we wouldn’t have succeeded.如果没有你的帮助，我们不会成功的。4、If虚拟条件句的倒装形式，即把were, had, should置于句首。例：Were I in school again (= If I were in school again), I would work harder.如果我能再上一次学，我会学习得更努力。Had you asked me, I would have told you. (=If you had asked me,…)如果你问我，我会告诉你。
joyzhou512
虚拟语气的本质是假设。
假设分为可能性大的假设（真实条件句）和可能性小的假设（非真实条件句——虚拟语气）。
英语使用真实时态表达真实条件句，英语使用非真实时态表达非真实条件句——虚拟语气。
例句：
1. You can get all the nutrition you need for much less money if you shop carefully.
如果你仔细购物，你可以用更少的钱得到你需要的所有营养。——真实条件句
2. If I were a bird, I would fly to you.
如果我是一只鸟，我就飞到你身边。——非真实条件句
英语表达虚拟的方式是时间提前，即用谓语的过去形表达虚拟，即：用过去表达现在，用过去的过去表达过去。
虚拟语气的本质也是委婉。
以上就是英语虚拟语气思维的核心。 关于虚拟语气更细致的内容请参考百家号专栏【英语思维：10小时建立完美英语语法体系】
清风百荷
虚拟语气一、考点聚焦1、虚拟语气用于条件状语从句中（1）表示与现在事实相反的假设,条件状语从句中的谓语动词用“过去式（be动词的过去式用were）”,而主句中的谓语动词用“would / should/ could / might + 动词原形”.如：\x09If I were a boy, I would join the army.\x09If the had time, she should go with you.\x09（2）表示与过去的事实相反,条件状语从句中的谓语动词用过去完成时,主句中的谓语动词则用“would / should / might / could + have +过去分词”.如：\x09If he had taken my advice, he would have succeeded in the competition.\x09（3）表示与将来事实相反,条件状语从句中的谓语动词一般过去时或should(were to) + 动词原形,而主句中的谓语动词则用would / should/\x09could might + 动词原形.如；\x09If it were to rain tomorrow, the football match would be put off.\x09（4）当条件状语从句表示的行为和主句表示的行为所发生的时间不一致时,动词的形式要根据它所表示的时间作相应调整.如：\x09If they had worked hard, they would be very tired.(从句说的是过去,主句指的是现在)\x09以下表格是虚拟语气用于条件状语从句中时,主句和从句谓语动词的形式：\x09条件状语从句\x09主 句与过去事实相反\x09had + 过去分词\x09should /would/could/might + have + 过去分词与现在事实相反\x09一般过去时(be用were)\x09would/should/could/might + 动词原形与将来事实相反\x09一般过去时或should(were to) + 动词原形\x09Would/should/cold/might + 动词原形\x09有时侯在使用时可省略if,句子则可换成下列形式,即“were / had / should +主语”.如：\x09Were I a boy, I would join the army.\x09Had he taken my advice, he would have succeeded.\x09Were it not for the expense, I would go to Britain.\x092、虚拟语气用于名词性从句\x09（1）虚拟语气在宾语从句中的运用.\x09①“wish + 宾语从句”表示不能实现的愿望,译为“要是……就好了”等.表示现在不能实现的愿望,从句中的谓语动词用一般过去时；表示将来不能实现的愿望,从句中的谓语动词用“would/could + 动词原形”；表示过去不能实现的愿望,从句中的谓语动词用“had + 过去分词”或“could(should) + have + 过去分词”.如：\x09I wish it were spring all the year round.\x09I wish I had known the answer.\x09I wish I could fly like a bird.\x09②在表示建议、要求、命令等的动词suggest、advise、propose、demand、require、insist request、command、order等后的宾语从句中,谓语动词用should + 动词原形或是动词原形.如：\x09She suggested we (should)leave here at once.\x09The doctor ordered she should be operated.\x09（2）虚拟语气在同位语从句和表语从句中的运用.\x09作表示建议、要求、命令等的名词advise、idea、order、demand、plan、proposal、suggestion、request等的表语从句和同位语从句,从句中的谓语动词用“（should） + 动词原形”.如：\x09His suggestion that we (should)go to Shanghai is wonderful.\x09My idea is that they (should)pay 100 dollars.\x09（3）虚拟语气在主语从句中的运用.\x09在主语从句中,谓语动词的虚拟语气用“should + 动词原形”的结构,表示惊奇、不相信、理应如此等.如：\x09It is necessary(important, natural, strange, etc.)that we should clean the room every day.\x09It was a pity (a shame, no wonder, etc.)that you should be so careless.\x09It will be desired(suggested, decided, ordered, requested, proposed, etc.)that she should finish her homework this afternoon.\x09注意：这种从句表示的是事实.如果说人对这种事实表现出惊奇的情感,就可用虚拟语气.反之,如果不表示惊奇等情感,that从句也可用陈述句语气.如：\x09It is pity that you can’t swim.\x093、虚拟语气在其他场合的运用\x09（1）虚拟语气在as if/as though、even if/even though等引导的表语从句或状语从句中,如果从句表示的动作发生在过去,用过去完成时；指现在状况,则用一般过去时；指将来状况则用过去将来时.如：\x09He did it as if he were an expert.\x09Even if she were here, she could not solve the problem.\x09（2）虚拟语气用于定语从句中.\x09这种从句常用于句型“It is (high)time (that) … ”中,定语从句的谓语动词用一般过去时(be用were)或should + 动词原形,意思是“(现在)该……”.如：\x09It’s time that I picked up my daughter.\x09It’s high time we were going.\x09（3）虚拟语气用在if only引导的感叹句中.如：\x09If only I were a bird.\x09If only I had taken his advice.\x09（4）虚拟语气在一些简单句中的运用.\x09①情态动词的过去式用于现在时态时,表示说话人谦虚、客气、有礼貌或语气委婉,常出现在日常会话中.如：\x09It would be better for you not to stay up too late.\x09Would you be kind enough to close the door?\x09②用于一些习惯表达法中.如：\x09Would you like a cup of tea?\x09I would rather not tell you.
