基础英语教学中的虚拟条件句及其变体，本文主要内容关键词为：变体论文,英语论文,条件论文,基础论文,教学中论文，此文献不代表本站观点，内容供学术参考，文章仅供参考阅读下载。
动词是学习英语词法的重点，语气是学习动词的难点，而虚拟又是学习语气的要点。因此，英语词法之重在动词，动词之难在“语气”，语气之要在“虚拟”。虚拟语气（subjunctive mood）是专门表达“假设意义”（hypothetical meaning）及其他“非事实意义”（non-factual meaning）的动词形式。简而言之，虚拟语气是动词的特殊形式，用来表达说话人难以实现或不可能使之成为事实的意愿、建议、请求、意图、惊奇、设想等情境。虚拟语气可分为条件式，即虚拟条件句（主要用于状语从句）、命令式/建议式（主要用于名词性从句）和其他类别。在各种类型的虚拟语气中，虚拟条件句是学习的基础，它分为基本形式和几种主要变体。前者结构相对较固定，类似公式，易于学习，后者则结构多变，形式多样，不易掌握。因此，在基础英语教学中，必须熟练掌握虚拟条件句的基本形式并有效识别各种“变体”。
一、虚拟条件句的基本结构与类别
英语虚拟条件句的基本形式由if引导的非真实性条件从句加上主句构成，为了表达虚拟功能，从句和主句谓语动词都要作特定形式的变化。由于人类生活需要经历过去、现在和将来三个不同时间节点，虚拟条件句也随之分为上述三种类型，各自结构及动词形式如表1所示。
虚拟条件句的三种基本形式对应的典型例句如下：
1.与现在事实相反的假设。（1）If I had the chance，I would have another try.如果我有这个机会，我定会再试试。（事实是我没这样的机会，不可能去试）（2）If I were you，I would have a sleepless night.如果我是你的话，我会失眠。（事实是我不是你，不可能会失眠）
2.与过去事实相反的假设。（1）If he had told you the fact that day,you would have grasped the precious opportunity.如果那天他把事实告诉你的话，你会抓住那个宝贵的机会。（事实是他没告诉你，机遇失之交臂）（2）If we had known the truth at that time，we would have made greater progress.如果我们当时了解真相，就会取得更大进步。（事实是，我们当时不解真相）
3.与将来情况相反的假设。（1）If they got/should/were to get the specific information tomorrow,they would get you informed soon.如果他们明天能得到相关消息，定会首先通知你。（事实是他们不能得到消息）（2）If you were/should/were to be the president of USA tomorrow,what would you do first? 如果你明天当上美国总统，首先将会做什么？（事实是，明天你不可能当上总统）
二、虚拟条件句的各种常见变体
1.省略if倒装式。如果有should，were或had出现在虚拟条件句的从句部分，则常省略该从句引导词if，并将should，were或had提到句首引起部分倒装。如：（1）Should it snow（If it should snow），we could not go out for picnic.如果明天下雪（事实是明天不会下雪），我们就不能外出野炊。（2）Were he in my position（If he were in my position）,he might act differently.如果他遇到我这种情况，他可能会做出相反的举动。（3）Had I taken your words that day（If I had taken your words that day）,I would have suffered a lot.如果我那天听了你的话，就会倒大霉。以上三例分别是对将来、现在和过去的虚拟，从句分别用到should，were和had。
2.委婉替代式。有时虚拟条件不直接通过if 引导词引出，而是借助部分介词或介词短语、不定式或动名词短语、特定抽象名词或并列句型以及上下文等形式表示出来，这种情况也称委婉或含蓄虚拟条件句。这类常见功能词有：without，with,but，but for/that（倘若），given more time,given,given that（如果被给），or，or else，otherwise（否则，要不然），unless（除非，如果不），supposing,supposed that（如果），等等。如：（1）Without solar power（=If there were no solar power）,our life would not be so green today.如果没有太阳能，我们就不能享受今天的绿色生活。（2）God would have helped you,but you was so lazy（=if you had not been so lazy）.如果你当初不是太懒，上天定会助你。（3）But for the heavy rain（=If it had not been for the heavy rain）,we should have delivered the goods on time.如果不是那场大雨，我们定会准时送货。（4）They' re really busy（=If they were not busy）,otherwise they would go traveling with me.如果他们不忙，就会和我一同出去走走。（5）Meeting in China（=If they had met in China）,they might have established a friendship.如果他们当时能在中国相遇，说不定还能建立一段友情。（6）To keep their promise（=If he were to keep their promise to each other）,they would love each other till death do them apart.如果他们铭记彼此的承诺，就会享受忠贞不渝的爱情。（7）One more step forward（=If you had moved one more step forward），and you might have seen the God.如果你当时再前进一步，就可能命丧黄泉。
3.错综时间式。有时虚拟条件句的从句和主句虚拟的时间不一致，这时从句和主句谓语动词的变化形式需要根据各自动作发生的时间来确定，这种不一致情况也称错综时间条件句。在这种虚拟条件句中，要避免前文所列三种基本形式中主句和从句动词“公式型”思维定势的干扰。如：（1）If I had studied harder in my school days,I might be sitting in a comfortable office now.如果我当初上学时用功点儿，如今也许能舒服地坐办公室了。（2）If you had turned to your advisor for help last night,you could cope with the situation now.如果你昨晚能及时向导师求教，现在就能胸有成竹了。（3）If they had followed my suggestion,they would not be in a dilemma now.如果他们当时听我一句忠言，现在就不会进退维谷了。
4.if only强化式。虚拟条件句的这种强化式一般用if only引导词代替if，表示在说话人看来与过去事实、现在事实或将来的情况相反的强烈愿望或遗憾，相应的谓语动词分别用过去完成时表对过去、动词过去时表对现在以及“could/would+动词原形”表对将来的强化虚拟，一般译作“要是”或“只要”。如：（1）If only you were a little braver，it would be more much better.如果再勇敢一点就好了。（对现在的虚拟）（2）If only we had been told the truth，we would have taken the chance.如果我们当时了解真相，定能抓住机遇。（对过去的虚拟）（3）If only I could do the experiment one day,I would do it oppositely.如果我将来能做这个实验，我会反其道而行。（对将来的假设）
值得注意的是，在强化式变体中往往习惯将if only虚拟条件句单独使用，表示一种特定背景下的强烈的假设性祈愿或期盼，动词形式与虚拟条件句基本形式中所列三种情况相同，常译作“要是……就好了”或“要是……该多好”。如：（1）If only I were in my hometown!（对现在的祈愿，事实是此时身处异域他乡）（2）If only they had seen each other ten years ago!（对过去的祈愿，抒相见太晚的遗憾）（3）If only I could fly in the space some day!（对未来的美好憧憬：遨游宇宙）
三、虚拟条件句及其变体在考试中的应用
下文从近五年高考试题中精选部分实例予以证实。
1.基本形式的应用。在虚拟条件句的基本式中，主句和从句标记明显，谓语动词形式相对固定，因而难度较小。（1）If I had nothing but money,I would start to travel around the world right now.如果我不是富到只缺钱，现在立马就去环游世界。（2）If he had taken my advice at that time,he might have got the job he applied for.如果他当时听了我的建议，说不定就已得到那份工作。（3）Jenny Walker considers if she were to go abroad she would probably be able to use English as frequently as she wants.詹尼·沃克认为如果出国（事实是她鲜有可能），就能随时随地用英语。以上三例分别是对现在、过去和将来的虚拟，主句和从句结构完整，标记明显。
2.各种变体的应用。虚拟条件式的各种变体结构多样、形式多变，深受英语考试的青睐，但万变不离其宗，下文是关于四类变体的部分实例：（1）Should pure water perish from the earth one day,there would hardly be any life on this planet.（2）Were we to meet on another planet 30 years later,what situation would you imagine?（3）The billions of calculations involved,had they been done by hand,would have lost all practical value by the time they were finished.以上三例为省略if的倒装式变体，分别将should,were和had提到句首省略if引起倒装。（4）Without the dreams of the youth,this invention might have been postponed for a century.（5）He was very upset yesterday,otherwise he would have come to the party.（6）We didn't know her address,or we would have paid a visit to her.以上三例为含蓄替代式变体，分别用without,otherwise和or引出。（7）Had Paul received six more votes in the last election,he would be our chairman now.（8）If we hadn't met Henry until recently,you'd think the photo was strange.（9）If you hadn't hurried to help me when I was in trouble,I wouldn't be in such comfort now.以上三例为错综时间混合式变体，都跨越过去和现在两个不同时间。（10）If only I had gone with you ten years ago!（11）If only we had a car! I'm tired of walking in such hot weather.（12）If only the organization would approve the applications and put them into practice!以上三例为if only强化式变体，表达了对过去、现在和将来的祈愿。
限于篇幅，上文仅选取了部分题目来证实虚拟条件句及其变体的结构和应用。其实，英语虚拟条件句及其变体不仅是英语考试中的要点和难点，而且是人们现实生活中抒发遗憾和缓解压力的必需品。因此，了解并掌握它必将受益。