英语条件状语从句㈢

取录自《英语自学参考系列·句法手册》 第五章  第四节 条件 方式状语从句

英语自学参考系列 句法手册   第五章   英语复合句及并列句  (简写本)

编者  川竹 樑翁

第四节之英语条件状语从句㈢

（续前：一、英语条件状语从句2. 条件状语从句引导词）

3. 虚拟条件句

上面所讲的条件状语从句，都属于真实条件句的范畴——真实条件句所假设的内容是有可能发生的。现在我们再讲讲非真实的虚拟条件句。虚拟条件句通常只由if引导，它所表达的内容是与事实相反或不大可能会发生事情。

⑴虚拟条件句三种基本类型

①与现在事实相反——若与现在事实相反，所用句式主干：

If +从句主语+过去式动词谓语【be用were】…，主句主语+ should／would／could／might +动词原形…

例：If I were a bird, I would fly to you. 如果我是只小鸟，我将飞向你的身旁。

If you took a taxi, you’d get there quicker. 如果你坐出租车去，你可以快一点到那里。【但你不坐】

If I were you, I would tell them the truth. 如果我是你的话，我就会把真相告诉他们。【我绝对不可能是你】

If I knew her number, I could ring her up. 要是我知道她的电话号码，我就可以给她打电话了。【可惜我不知道】

 

②与过去事实相反——若与过去事实相反，所用句式主干：

If +从句主语+过去完成时动词谓语【had+过去分词】，主句主语+ should／would／could／might + have+过去分词…

例：If I’d left sooner, I’d have been on time. 要是我早点动身，我就准时到了【但我动身太迟了】

If we had had enough money, we would have bought the house.【遗憾的是钱不够】

如果我们有足够的钱的话，我们就买下那座房子了。

If we had found him earlier we could have saved his life. 【可惜我们找到他太晚了】

要是我们当时早点找到他的话，我们就可以救活他。

 

③与将来事实相反——若与将来事实相反，所用句式主干：过去式动词谓语【be用were】

If +从句主语+ should／were to +动词原形，主句主语+ should／would／could／might +动词原形…

例：If she were to／should come, what should I say to her? 万一她来了，我该怎么对她说呢？

If he were to give me a ring, what should I answer? 假如他打电话给我，我该怎样回答？

If he were to go, would you go too? 如果他去，你也去吗? 【大概他不会去】

If I should ask him, I’m sure he’d help us. 如果我向他提出要求，肯定他会帮助我们。【不过我不打算这样做】

 

⑵关于虚拟句式的几点说明

①主句谓语中的should主要用于第一人称。would、might、could的大致区别是：would表示结果，might表示可能性，could表示能力、允许或可能性。

比较：If he had done otherwise, I should have thought him a rascal. 如果他那样做了，我就认为他是个恶棍。

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，你就能能够成功了。【could表能力】

 

②条件从句的谓语动词为be时，不管其主语为单数还是复数通常都用were，但在口语或非正式文体中的单数第一人称和第三人称后，也可用was，不过在 If I were you这样的表达中，通常还是以用were为宜。

例：If I was you, I would buy it. 如果我是你，我就买。【口语表达可用was】

If I was you I should wait a bit. 我要是你的话,，我就会等一会儿。

If my wife was young as you, it would be great. 要是我妻子像你一样年青该多好。

If I were you, I wouldn’t agree it. 我要是你，就不会同意这件事。【正式文体宜用were】

I should certainly be on my guard if I were you. 我要是你肯定会保持警惕。

 

③有时条件从句用would表示愿意。

例：If he would live on with me, I would be his better half. 要是他还愿意跟我过，我仍会做他的妻子。

If she would lay aside the habit of smoking, her health would improve. 要是她戒烟的话, 她的身体就会好起来。

If she would only be herself, she would be more liked by other girls.

只要她能充分控制自己，她便会更为别的女孩所喜欢.

 

④对于“与将来事实相反”的情形，请注意以下几点：

a).这里说的与将来事实相反，实为对将来情况的推测；因为将来情况的事实如何，一般无法事前确知。

b).虚拟条件从句谓语动词除用过去式外，有时也用“should+动词原形”【表示可能性极小，常译为“万一”】或用“were to+动词原形”【表示与将来事实相反的假设】。

例：If he should come, I would tell him the truth. 万一他来，我会把真相告诉他。

If she should marry Hight, she would mend her market. 如果她能同海特结婚，她就可以提高自己的社会地位。

If he were to come, I might have time to see him. 只要他来, 我就可能有时间见见

If he were to do it, he might do it the same way. 要是由他来做这事，他可能用同样的方法做。

c). 当条件从句使用“should+动词原形”这样的谓语时，主句谓语除可用“should／would／could／might+动词原形”这样的虚拟语气外，也可用陈述语气或祈使语气。

例：If I should see him, I’ll tell him. 万一我见到他，我就告诉他。【陈述语气】

If he should come, I will tell him the truth. 万一他来，我一定会把真相告诉他。

If it should rain tomorrow, don’t expect me. 万一明天下雨，就不要等我了。【祈使语气】

If it should rain tomorrow, don’t go with me. 要是明天下雨，就不要跟我一起去了。

总之，should在虚拟句中的使用有其特殊性，并不只限于用于第一人称。

 

⑶虚拟条件句的倒装

①有时连词if可省但虚拟句需半倒装 ——若是虚拟条件句中含有were或had，should等助动词或情态动词时，虚拟句连词if可以省略，但须将were、had、should提到句首而成局部倒装。

例：If you had come earlier, you would have met him. 如果你早点来，你就会见到他了。

→Had you come earlier, you would have met him.

Had I left【=If I had left】a little earlier, I would have caught the train. 如果我早一点走，我就赶上火车了。

Had I seen him then, I would have been very happy. 如果我再看见他，我会很高兴的。

Had he known her address, he would have gone to visit her. 如果他知道她的地址, 他就去看望她了。

If she were in charge, she would do things differently.  如果是她负责，她会是另一种做法。

→Were she in charge, she would do things differently.

Should it rain【=If it should rain】, the crops would be saved. 如果下雨，庄稼就有救了。

Should it rain tomorrow, we would cancel the trip. 如果明天下雨，我们将取消这次旅行。

If you should change your mind, no one would blame you. 万一你改变主意，谁也不会怨你。

→Should you change your mind, no one would blame you.

Were I you【=If I were you】, I would attend the meeting. 如果我是你, 我就要参加会议。

Were I to do【=If I were to do】the work, I should do it some other day 要是我做这项工作，我会改天来做。

 

②对于条件从句含有should而主句使用陈述语气或祈使语气的句子，也可以采用这种方法进行省略和倒装。

例：If I should be free tomorrow, I will come. 如果明天我有空我就来。

→Should I be free tomorrow, I will come.

If they should attack us, we’ll wipe them out completely. 假如他们进攻我们，我们就把他们彻底消灭干净。

→Should they attack us, we’ll wipe them out completely.

 

③有时候，被提到句首的had不是助动词，而是表“有”的实义动词。

例：If I had the time, I would go with him. 如果我有那时间，我就跟他去。

→Had I the time, I would go with him.

If I had my druthers, I'd go swimming. 如果我能选择的话, 我就去游泳.

→Had I my druthers, I'd go swimming.

 

④在这类倒装结构中，置于句首的were习惯上不能用was代替【有下例为证】。

例：If I were you, I would go to look for him.→Were I you, I would go to look for him. 如果我是你，就会去找他。

If he were here, everything would be all right.→Were he here, everything would be all right.

如果他在这儿，一切都会好的。

If I were in your place, I wouldn’t do that. →Were I in your place, I wouldn’t do that.

如果我处在你的位置，我就不会这样做。

If they were here now, they could help us. →Were they here now, they could help us.

如果他们现在在这儿，他们会帮助我们的。

 

⑤如果条件从句为否定式，注意要将not置于主语之后，而不置于主语之前。而且，在省略连词if的倒装形式的句首，不能用动词的缩略形式，如我们可说 Were I not to do., 但不能说 Weren’t I to do。

例：若不是有你的帮助，我仍会无家可归。

误：*Weren’t it for your help, I would still be homeless.

正：Were it not for your help, I would still be homeless.

又例：要不是我亲眼所见，我都不会相信的。

误：*Hadn’t I seen it with my own eyes, I would not have believed it.

正：Had I not seen it with my own eyes, I would not have believed it.

 

⑷混合虚拟语气——在含虚拟语气的同一个英语复合句中，有的主句和条件从句所表现的时间形式或语气形式并不一致，即虚拟语气混含有陈述语气，这种语法现象就是混合虚拟语气(mixing the subjunctive mood)。

①错综时间条件句——有时，主句与从句的动作发生在不同的时间，主句和从句谓语动词的虚拟语气形式便因时间的不同而不同，这种条件句叫做错综时间条件句(conditional sentences of mixed time)。错综时间条件句的绝大多数情况，从句或主句都有相关的时间状语；如果本句没有时间状语明确提示，也可以从对上下文理解中领悟出所指的不同时间。

例：If you had asked him yesterday, you would know what to do now. 【从句与过去事实相反,主句与现在事实相反】

如果你昨天问过他，今天就知道做什么了。

If I were you, I wouldn’t have missed the film last night．【从句与现在事实相反, 主句与过去事实相反】

如果我是你，我就不会错过昨天晚上的那部电影。

If it had rained yesterday【过去】，it would be very cold today【现在】。如果昨天下过雨，今天就会很冷了。

If you hadn’t watched that late movie last night【过去】, you wouldn’t be so sleepy【现在】.

如果你昨天晚上不那看夜场电影，你就现在不会这么睏。

If he had followed the doctor’s advice then【过去】, he would be quite all right now.【现在】

如果他当时听从了医生的建议，他现在就会好了。

If Paul received more votes in this election【现在】, he would be our chairman after May【将来】

如果保罗在选举中获得更多选票，五月份以后他就将是我们的主席。

 

②虚拟陈述混合句——人们在使用语句时，往往是根据所述情况是否“虚拟”来决定是否使用虚拟语气。有的语句，或者是为了实际需要，或者是为了语气委婉，既用有虚拟语气，也用了陈述语气，这样同时包含有虚拟假设和事实陈述两种语气的句子就是虚拟陈述混合句(virtual representations mixed sentence)。

a).在同一句话中，若是表示与事实相反的假设或不太可能实现的假设或愿望，就用虚拟语气；如若表示实实在在的事实，便用陈述语气。

例：If it hadn’t been for your help, I really don’t know what I’d have done.

要不是你的帮助，我真不知会弄成什么样子。

Thank you very much indeed. If it had not been for your advice I really don’t know what I should have done.

真的是太感谢你了。要不是因为你给我提的建议，我真不知道自己做出了什么蠢事来。

虽然两句中的 if it hadn’t been for your … 和what I’d have done均用了虚拟语气【均表示与过去事实相反的假设】，但句中的“我不知道”不能用虚拟语气，因为I don’t know是在陈述现在的事实。

 

b). 当条件从句含有should时，有时可以在主句使用祈使语气或陈述语气，以使语气更客气、更委婉。

例：If she should be interested in this, I’ll phone her. 如果她对此有兴趣，我可以给她打电话。【主句陈述】

If you should write to her, send her my love. 如果你给她写信，请代我向她致意。【主句祈使】

If these biscuits should arrive in a damaged condition，please inform the factory at once.

饼干运到时如有损坏，请立即通知本厂。

其实，这样用的句式更接近陈述语气，因为，如果将条件从句中的“should+动词原形”改为一般现在时，也完全可以，只是语气上没那么委婉了【即更直接些】。

例：If she is interested in this, I’ll phone her. 如果她对此有兴趣，我就给她打电话。

If you write to her, send her my love. 如果你给她写信，请代我向她致意。

If these biscuits arrive in a damaged condition please inform the factory at once.

饼干运到时如有损坏，请立即通知本厂。

值得注意的是，这样用的条件从句不能用否定形式，除非它是倒装的【或改为一般现在时】。

例：你若不希望我们的代理人去造访，请告知。

译：Should you not wish our agent to call, please let us know.【√(倒装)】

If you don’t wish our agent to call, please let us know. 【√(现在时)】

若：*If you should not wish our agent to call, please let us know.【×】

特别提示；若主句也用虚拟语气则句子性质改变。

如果这类句式的主句也使用虚拟语气，那便不全是语气委婉与否的问题，而是真正的虚拟语气问题【即与事实相反或不太可能成为现实的】。

例：If he should go away, I should be grieved. 他如离去，我就会感到悲伤。

If it should rain tomorrow, we should have to put off the match. 假若明天下雨，我们只好推迟这场比赛。

 

4. if虚拟句与if真实句比较

if既可引导一个真实条件状语，又可引导一个非真实条件状语从句，二者主要在以下三个方面有所不同：

⑴从句意义及谓语动词形式不同

如果该条件纯属假设，谓语动词用虚拟语气；有可能实现的条件则使用动词通常的陈述形式。

①非真实条件状语从句的谓语动词用动词过去式来表示与现在事实相反或难以实现的愿望，主句则用“would+动词原形”；而真实条件状语从句的谓语动词用动词的一般现在时表示一般或未来情形下的条件，主句用一般现在时或将来时。

比较：Oil floats if you pour it on water. 如果你把油倒在水上，它就漂浮在上面。【能实现的事实(真实句)】

If my husband were a woman, he would understand my feelings a bit better. 【丈夫不可能是女人(虚拟句)】“”

我丈夫是个女人的话，他就会更好一点儿理解我的感情了。

 

②非真实条件状语从句的谓语动词“had+过去分词”表示与过去的事实相反，主句用“would have done”；真实条件状语从句用一般过去时指过去的事实或用于间接引语中【可表示过去将来的情况】，主句用一般过去时或过去将来时。

比较：If Mike was a liar, it was for my sake.

如果迈克曾是一个撒谎的人，那也是为了我。【当时迈克极有可能撒了谎(真实句)】

If I had been a teacher at that time, I would have argued with him.

当时我要是老师的话，就和他争辩了。【事实上我当时不是老师(虚拟句)】

He said he would go there if it was fine the next day. 他说，如果第二天天气好他就去那里。

 

⑵从句所用情态动词含义不同

①If I／we／you／he／she +“should + 动词原形”或“were to +动词原形”或“动词过去式”，表示对将来情况的虚拟假设，即某事不会或不太可能发生，具有较大的试探性。

例：If you should run into Peter, please tell him he owes me a letter. 假如你碰见皮特，告诉他说他该给我写信了。

What would you do if war were to break out? 如果战争爆发，你会怎么办？

 

②if引导的真实条件状语从句，一般很少使用将来时态，但有时也可用情态动词will或would来表示“愿望【如果愿意…】”，甚至可用这种方式提出请求。

例：It’ll make me very happy if you’ll accept it. 如果你愿意收下它我会很高兴的。

If you will hold my bag, I’ll open the door.【i.e. please hold my bag】 如果你愿意替我拿包，我就开门【即，请替我拿包】。

If you will wait a moment, I’ll go and tell the manager that you are here.

如果你愿意等一会儿，我就会去告诉经理说你来了。

 

⑶从句与其他句型转换形式不同

①非真实条件状语从句中的if可省略，从句可以用倒装语序；而真实条件状语从句一般不可以这样做

例：If he were my son, I would beat him. 如果他是我的儿子，我就打他了。

→Were he my son, I would beat him. (√)

If you touch me again, I'll call the police. 你再碰我，我就叫警察。

→Do you touch me again, I'll call the police. (×)

 

②真实条件状语从句可以转换为“祈使句+and +陈述句”，而非真实条件状语从句则不可以这么改写。

例：If you touch me again, I’ll call the police.→(You) Touch me again and I’ll call the police. (√)

If you work hard,you will be successful in time. 只要你努力，一定会成功。

→Work hard,and you’ll be successful in time./

If you follow your doctor’s advice, your cough will get worse如果你听了医生的话，你的咳嗽会变得更糟。

→Follow your doctor’s advice, and your cough will get worse．

 

③真实条件状语从句的否定式可与unless ...转换，而非真实条件状语从句的否定式却不能。

例：If it doesn’t rain tomorrow, I’ll plant the flowers. 如果明天不下雨，我就把花栽上。

→I’ll plant the flowers unless it rains tomorrow.【√】

If it hadn’t been for you, I would have failed in the exam. 如果不是你的话我就不会通过考试了。

→Unless it had been for you, I would have failed in the exam【×】

 

⑷真实条件句有的可省略——也就是说，虚拟条件句一般不见省略现象。

由if或unless引导的条件状语从句，若其主语与主句主语相一致，且谓语动词含be，则从句的代词主语he、she、it或they及相应形式的be动词，可以省略。

①if条件句中的省略——常用的省略式：if possible、if necessary、if true等。

例：Come along with me if (it is) possible. 如果有可能和我一起去吧.。

A single room with a bath, if possible. 如果可能，要一间带浴室的单人房。

If (it is) necessary, ring me at home. 如果有可能，朝我家里打电话吧。

If necessary, please warehouse the goods. 如有必要，请将该货存入仓库。

You can use these reference books, if necessary. 如果必要，你可用这些参考书。

If (it is) true, this will casue us a lot of trouble. 如果是真的，这会给我们带来很多麻烦。

If true then full width letters will be inputted by default. 启用之后，会预设输入全型英文字母。

 

②如果if从句主语同于主句主语，且从句谓语含助动词be，那么，该从句“主语+be”可以省掉，但不见得一定要省略。

例：He will come if (he is) asked. 如果叫他来，他就来。

Send the goods now if (they are) ready. 货物如果准备好了，请送过来。

Thin wires easily melt if (they are) made of copper. 如果用铜制细导线极易熔化。

Grapes／Fruit juices ferment if (they are) kept too long. 葡萄／果汁若是放久了，就会发酵。

 

③如果if从句是“there be”句，“there be”也可省略。当然，这类省略只说是可能可以的，并不一定得省略。

例：If (there is) any trouble, do let me know. 如遇到麻烦，务必告诉我。

If (there is) anything new, report at once. 如有新的情况，请火速报告。

If (there are) any lessons to be drawn, what are they? 如果说到教训，则教训在何处?

There are few people nowadays, if (there are) any, who remember him. 很少有人能记起他了。

 

④unless条件句中的省略——省略原则与if从句同。

例：Unless (being) rich, I am not going to buy a house. 除非有钱，要不然我是不会买房子的。

He won’t go there with us unless (he is) invited. 除非受到邀请，否则他不会和我们一道去那里。

You should stay where you are, unless (you are) asked to leave. 你应呆在你现在的地方不动，除非叫你动。

Don’t pull the chicken switch, unless (you are) absolutely necessary. 除非绝对必要，请不要碰紧急弹射按钮。

（条件从句续完）