1、高考英语核心语法学案：虚拟语气用来表示说的话不是事实，或者是不可能发生的情况，而是一种愿望、建议、假设的语气叫虚拟语气。(一)if 主从句中的虚拟语气【完成例句】 (1)如果我是你，我会接受邀请的。 If I were you, I should accept the invitation. (2)如果我有空，我就去那儿。If I had time, I would go there. 【结论 1】从句谓语用一般过去时(be 多用 were) 条件与现在事实相反 主句谓语用 would / should / could / might动词原形【完成例句】 (3)如果你早点来，你就不会错过那辆公
2、共汽车了。If you had come earlier, you couldnt / wouldnt have missed the bus. (4)如果他昨天见到了你，他就会还你的书的。If he had seen you yesterday, he would have returned your book. 【结论 2】从句谓语用 had done条件与过去事实相反 主句谓语用 would / should / could / mighthave done【完成例句】 (5)万一明天下雨，运动会就推迟。(事实上明天下雨的可能性不大。)If it should rain / were t
3、o rain / rained tomorrow, the sports meet would be put off.(6)万一杯子掉下来会打碎的。If you dropped / should drop / were to drop the glass, it would break. 【结论 3】从句谓语用一般过去时(be 多用 were)或 should 动词原形 / were to do条件与将来事实相反主句谓语用 would / should / could / might动词原形【疑难 1】含蓄虚拟句(即含有 without / but for, otherwise / or 等词
4、的句子)【例句观察】 Human beings would die without water. (Human beings would die if there were no water. )I couldnt have succeeded but for your help. (I couldnt have succeeded if you hadnt helped me.)I had no money then. Otherwise I would have bought that book. (If I had had money then, I would have bought
5、that book. )【疑难剖析 1】含有 without / but for，otherwise / or 等词的句子谓语结构等同于 if 主从句中主句的谓语结构。与现在或将来事实相反would / should / could / might动词原形与过去事实相反would / should / could / mighthave done【疑难 2】含有 had，should，were 这三个词的虚拟条件状语从句Had they had time(If they had had time)， they would have certainly come to help us. Shou
6、ld it be fine(If it should be fine)，we would go for an outing. Were I you(If I were you), I would go. 【疑难剖析 2】含有 had，should，were 这三个词的虚拟条件状语从句，在正式或书面语言中可将 if 省略，把 had，should，were 提前放到句首，变为部分倒装。【疑难 3】if 混合虚拟条件从句(即主从句分别与不同的事实相反)If the weather had been finer, the crops would be growing still better. If
7、 you had followed the teachers advice, you wouldnt be in hospital. 【疑难剖析 3】if 假设条件从句谓语动词发生的时间与主句所假设的谓语动词不一致，叫做错综条件虚拟语气。主句和从句的谓语动词要依照假设的时间而定。(二)用虚拟语气，从句中谓语时态相应推后(即用相应的过去时态)的五种句型【完成例句】(7)他多么希望自己是只鸟。How he wishes that he were a bird. (8)我希望昨晚看了那部电影了。 I wish I had seen the film last night. (9)我们希望有一天能住在
8、月球上。We wish we would live on the moon one day. 【结论 1】在动词 wish 引导的宾语从句中， 表示不太可能实现的愿望，从句必须使用虚拟语气。表示愿望与现在事实相反 从句用一般过去时(did 或 were)表示愿望与过去事实相反 从句用过去完成时(had done)表示愿望实现的可能性很小 从句常用 could / might / would do【完成例句】(10)我宁可你现在不在我身边。 I would rather you were not here with me now. (11)我宁可你没做过那件事。I would rather yo
9、u hadnt done that. 【结论 2】would rather / prefer that从句(从句用虚拟语气) 表示愿望与现在事实相反 从句用一般过去时表示愿望与过去事实相反 从句用过去完成时【完成例句】(12)她英语说得好像她就是纽约本地人一样。She speaks English as though she were a native of New York. 【结论 3】as if / though 从句中谓语用相应的过去时态 (等同于 wish 从句用法)。【完成例句】(13)要是你没告诉我那个消息就好了。If only you hadnt told me the new
10、s. 【结论 4】if only (要是就好了 )，句中谓语用相应的过去时态(等同于 wish 从句用法) 。【完成例句】 (14)我本来可以帮你忙的，即使我当时很忙。Even though I had been very busy then, I would have helped you. (15)即使我现在能跑，我也不会那样做。Even if I might run, I wouldnt do that. 【结论 5】even if / though 从句中的虚拟与现在事实相反 用 should动词原形与过去事实相反 用 had done(三)从句中所用的虚拟语气结构为 should 动
11、词原形，should 可以省略。【例句观察】 The doctor suggests I (should) exercise every day. 医生建议我每天做运动。(宾语从句)It is suggested that I (should) exercise every day. 我被建议每天做运动。(主语从句)The doctors suggestion is that I (should) exercise every day. 医生给我的建议是每天做运动。(表语从句)The doctors suggestion that I (should) exercise every day s
12、ounds reasonable. 医生要我每天做运动的建议听起来挺合理的。(同位语从句)【结论 1】名词性从句中，表示 “建议，命令，要求”等意义时，名词性从句用(should) 动词原形。一个坚持：insist两个命令：order, command (名词是 order, recommendation)三个建议：advise, suggest，propose(名词是 advice, suggestion, proposal)四个要求：demand, require, request, desire(名词是 demand, requirement, request, desire)注意：1.
13、 suggest 意为“表明，暗示” 时，不用虚拟语气；如：His face suggested that he was very sad. 2. insist 意为“坚持认为，坚持说”时，不用虚拟语气；如：The man insisted my little brother was a thief.【例句观察】我们应该掌握电脑知识，这是很重要的。It is important that we (should) have a good knowledge of computer science. 你居然没参加会议，真是可惜。It is a pity that you (should) be a
14、bsent from the meeting. 他竟然是名医生，我们很惊讶。We are surprised that he (should) be a doctor. 【结论 2】虚拟语气用在“Its形容词 / 名词that”这类句型中，表示说话人“强烈” 的感情色彩，此时，从句用 should 动词原形 / should have done (表示动作在过去已经发生)，should 可译为“应该；居然，竟然”。should 可以省略。It is important / necessary / strange / surprising / funny / natural that从句It i
15、s a pity / a shame / an honour / no wonder that从句主语 be sorry / disappointed / surprised that从句【例句观察】以防错过第一班车，我们一大早就起床了。We got up early for fear that we should miss the first bus. We got up early lest that we should miss the first bus. 【结论 3】在 in case, for fear (that), lest 等引导的状语从句中，谓语动词用“should动词原形
16、”。(四)几种特殊用法1. 某些简单句的固定句型Heaven help him!God bless you!May you succeed!Long live the Peoples Republic of China!2. 某些固定的词组和句型was / were supposed to have done 理应做was / were to have done 本计划做had thought / believed， but本以为had planned / intended，but本计划，本打算had wished / hoped，but本希望Its (about / high)time that从句，某人该做某事了
