一．虚拟语气四步判断
1.是否虚拟，是前提
分析对某一情形的描述是否该用虚拟语气，表达的是真实情况还是与事实相反的假设。
2.何时虚拟，时间变量
判断虚拟的时间，是对现在，将来，过去这三个时间中的哪个时间虚拟。
3.主句虚拟，主句变量
主句的三种不同时间谓语，现在和将来用would do,过去的用would have done。
4.从句虚拟，从句变量
从句的三种不同时间谓语，将来用were to do 或should do,过去用Were或did,过去完成时had done或had been。
二．将来虚拟，谈论的是不大可能的情形，而不是一个与事实相反的情形
If it were to rain, I would stay home.万一要下雨，那我就呆在家里。将来虚拟，表明说话人认为将来不太可能下雨
If it rains, I will stay home. 如果下雨了，我就在家呆着。表明说话人认为下雨的可能性比较大
不同语气的选择反映了说话人对未来下雨的可能性的信心程度不同
三．现在虚拟，从句使用一般过去时，如果是be动词则不论句子的主语是单数还是复数都用复数形式were而不是was. 主句用would/should +动词原形。
If I become President, I will make American stronger at home and more respected in the world.
如果我当了美国总统，我要让美国变得更强大，在国际上更受尊重。希拉里竞选时用真实条件的陈述语气来表明对自已未来总统竞选获胜的信心。
If I became president, I would make American stronger at home and more respected in the world.
如果希拉里用虚拟语气恐怕连支持她的选民都要改为支持她的竞争对手了。
四．过去虚拟，主句的谓语采用would have done,从句的谓语用过去完成时态had done
If he had known about the win, I would never have known whether it was me or the money he would want to stay with.如果他先知道我赢得了这个大奖，那我就无从知晓他和我交往是因为爱我，还是因为爱我的钱。
I don’t know what I have done if he hadn’t answered yes.如果他当时没有回答说爱我，我真不知道该怎么办。
五．混合虚拟
1.主句现在( would +动词原形)+从句过去（had done）,要判断所谈论的情形是否与事实相反，还得分别判断主句和从句虚拟的时间。
A:What an accident! If you had been careful, things would not be as they are.
多糟糕啊！如果你当初小心点情况就不会像现在这个样子了。
B：What do you mean, it was my fault? It it were, surely I would take all responsibility.
你这是什么意思啊，这都是我的错吗？如果是，我当然会负全责。
解析：A抱怨B当初没有小心。主句是对现在的虚拟，谈的是眼前糟糕的处境。B回答中也使用了虚拟语气，主从句都是对现在的虚拟，言外之意：这不是他的错，所有他不会承担任何责任。
If I had studied English at school, I could read the English novel now.
如果我在学校学过英语，我现在就能读英文小说了。
2.主句过去（would have done）+从句现在(were/did)
如果我不爱她，我就不会娶她，言外之意：我当然爱她，要不我就不会娶她了
正确表达：If I didn’t love her(对现在虚拟), I wouldn’t have married her.（对过去虚拟）
If I hadn’t loved her（对过去虚拟）, I wouldn’t have married her.（对过去虚拟）
结婚的时候是爱她的，要不然当时就不会娶她。言外之意：当时能和她结婚，是因为当时爱她，但现在已经不爱了（所以离婚吧）
If I didn’t love her（对将来虚拟）, I wouldn’t marry her.（对将来虚拟，表示两人还没有结婚）
如果我不爱她，我将来就不打算和她结婚了，是以男朋友的身份说的。
恢复语境：
A：Do you love your girlfriend ?你爱你的女朋友吗？
B: If I didn’t love her, I wouldn’t marry her. 如果我不爱她，我将来就不打算和她结婚了。
在日常中对话中，我们往往会这样责怪别人：“如果你真的理解我的话，你当时就不可能说出那种话了。
If you knew me better, you wouldn’t have said that.(主句过去，从句现在)
六．倒装虚拟
当If 引导的条件句省去if时，可将Should, had或were置于句首
Should I win the lottery, I would buy a car.=If I should win the lottery, I would buy a car.如果我能赢得大奖，我就会买一辆车。（主将来，从将来）
Were he to tell us everything, we could try to solve his problem.=If he were to tell us everything, we could try to solve his problem.如果他把一切都告诉我们，我们就能想办法解决他的问题。（主现在，从将来）
Had such a disaster had occurred, the damage would have been incalculable.=If such a disaster had occurred, the
damage would have been incalculable.如果这场灾难发生，损失将难以估量。（主过去，从过去）
七．跳层虚拟
1.陈述句（陈述语气）+or（or else/otherwise）+虚拟主句（虚拟语气）,是虚拟主句
a.主语+一般现在时的谓语形式，or+主语+would do，表示对现在事实的虚拟
b.主语+一般过去时的谓语形式，or+主语+would have done，表示对过去事实的虚拟
We didn’t know his telephone, otherwise we would have telephoned him.=We wouldn’t have telephoned him if we had known his telephone number.
我们不知道他的电话，要不然我们当时就会给他打电话了。
2.虚拟主句(虚拟语气)+but+陈述句(陈述语气)
a.主语+would do, But +主语+一般现在时的谓语形式，表示对现在事实的虚拟
b.主语+would have done，But+主语+一般过去时的谓语形式，表示对过去事实的虚拟
Would 可换成should,might或could.关键标志词是but,随着but一转折句子语气由虚拟变为不虚拟，即but将句子一分为二，but前面部分的句子用虚拟语气，but后面部分的句子用陈述语气。
He would put on weight, but he doesn’t eat much.=He would put on weight if he ate much.
他本来是会发胖的，但是他特别注意节食，从来不会多吃。
这里不能用didn’t，而是doesn’t，因为前面的would不是表示过去时态，而是表示对现在事实的虚拟。
I would have gone to visit him in the hospital, had it been at all possible, but I was fully occupied the whole of last week.如果真的有可能，我本来是想去医院看望他的，但是我上周整个一周都很忙。
A safety analysis would have identified the target as a potential danger. Unfortunately, it was never done.若有安全分析，就可以发现这个潜在的隐患，但遗憾的是，并没有做安全分析。
有时不用but来表示转折，而是用其它副词，如unfortunately.
八．名词从句如何使用虚拟
1.名词从句虚拟无论其主句的谓语动词是何种形式，从句的谓语形式均为should+动词原形，其中should可以省去。注意此处不是用would而是用should.
I suggest that we should go tomorrow. 我建议我们明天走
I suggested that we should go the next day.我当时建议我们第二天走。
从句中谓语的时态（should
go）并没有受主句谓语时态（suggest,suggested）的影响。
名词从句的虚拟最终归结为：记住相应的标志词即可，一旦主句中出现某一个标志词，就要注意其从句谓语必须用（should）+do.
如下面这类词的宾语从句中。
ask,advise,beg,command,demand,decide,desire,determine,insist,move,order,prefer,propose,require等。
2.it is +形容词或过去分词或特定的名词+that的主语从句
a.形容词 astonishing,amazing,advisable,appropriate,crucial.desirable,essential,sorry,shocked等,这些形容词表示一个人对事件的反应。
It is natural that I should dwell upon his successes rather than upon his failures.
我宁愿强调他成功的地方，而不愿突出他的失败之处，这是很自然的。
It is quite natrual that the customs of all national minorities be respected.
b.过去分词 decided ,desired,demanded,ordered,requested等
It is requested that all members be present at the meeting.要求所有的成员都出席这个会议。
c.特定的名词 advice,decision.desire,demand,suggestion,motion.pray,resolution,wish等
It is my proposal that he be sent to study
further abroad.我建议，把他送到国外去学习。
d.在上述名词的表语从句和同位词从句中
The suggestion that the mayor present the prizes was accepted by everyone.由市长颁奖的建议被所有人接受了。
八．各种虚拟句型
虚拟语气分为非真实条件句和名词从句虚拟句两大类。
A.在wish后面的宾语从句中，表示说话者难以实现的或民事实违背的愿望，具有较强的感情色彩，可分别表示对现在，过去和将来情影的虚拟。
1.对现在的虚拟，表示对现状的愿望，从句的谓语动词用过去时。
I wish I were a litlle younger. 我希望我能够年轻点
I wish I could travel to the moon (but I can’t do that).我希望我能够登上月球（但实际上我不能）。
2.对过去的虚拟，对过去发生的事情表示遗憾或后悔，从句的谓语动词用过去完成时（had done）或 would/could +现在完成时。从句的谓语动语所表示的动作发生在主句的谓语所表示的动作之前。
I wish I had been there. 我真希望我当时在那。
I wish I could have gone wih you to the concert last night.我真希望昨晚能和你一起去听音乐会。
3.对将来的虚拟，对表将发生的事情表示祝愿，从句的谓语动词用would/could+动词原形。从句的谓语动词所表示的动作可能发生在主句的谓语所表示的动作之后。
I wish you would shut up.我希望你能闭嘴。
B.在if only感叹句中，用法与wish基本相同，可表示对现在，过去和将来的虚拟，只是比wish具有更强烈的感情色彩。
If only the rain would stop.但愿雨能停。（对将来的虚拟）
If only I were taller.我的个子要是能高一点就好了。（对现在的虚拟）
If only he had followed your advice.他要是听从了你的建议就好了！（对过去的虚拟）
C.在as if /as though 引导的从句中表示与现在事实相反或对现在的情况有所怀疑，谓语用过去时
I really don’t care for the way you’re speaking to me. It seems as if you were my father.
我真的非常讨厌你和我说话的方式。你听起来就好像是我爸爸。
表示与过去事实相反，谓语用过去完成时
It is becoming dark. It looks as if it’s going to rain. 天变黑了，似乎就要下雨了。
D.在It is (high ) time (that)从句中，该句型表示“该是做什么事的时候了”，含有“晚了一点”的意思，从句用过去时。
Don’t dawdle away your youth any more. It is time you thought about your furture.
不要再浪费青春了，你该考虑自已的将来了。
E.在would rather, would as soon,
would sooner, would prefer等从句中Would rather 后面可以接从句和接动词原形，而且would rather 表示将来，现在和过去时的谓语动词的不同形式。
would rather do sth. Would rather的后面接动词原形，可以表示对将来或现在的事件。意指“主语宁愿自已做某事”
He would rather stay at home than go the cinema tonight. 他今晚就想在家里呆着，而不想去看电影.
would rather have done sth.
Would rather 后面接动词完成式的用法，表示过去的事件。意指“主语宁愿自已过去做了某事，但实际上没有做。”
I took Sally to the cinema last night, but I would rather have been there alone.我昨晚带莎莉看电影去了，可是我还不如自已一个人去呢（真不该带她去）。
3. would rather sb. did.would rather后面接从句的用法，意指“主语宁愿让另一个人做某事”。这里从句的谓语用一般过去式，但表示的是现在或将来的事件，如同现在虚拟条件从句的谓语形式。
Don’t come tomorrow. I’d rather you came next weekend.明天就别来了，我希望你下周末过来。
would rather sb. had done. Would
rather后面接从句的用法，意指“主语宁愿别人过去做了某事，但实际上没有做”。这里从句的谓语用过去完成时表示过去的事件，如同过运虚拟条件从句的谓语形式。
I’d just as soon you didn’t speak rudely to her.我希望你不要那么粗鲁地对她说话。
网友评论