专题10 虚拟语气-备战2021年高考英语语法精讲PPT

语法专题十　虚拟语气 考试考点聚焦考点一　 虚拟语气在条件从句中的用法 主、从句的谓语动词形式： 从句 主句 与现在事实相反 动词的过去式(be的过去式一般用were) would/should/could/might＋动词原形 与过去事实相反 had＋过去分词 would/should/could/might＋have＋过去分词 与将来事实相反 1.动词过去式 2.should＋动词原形 3.were to＋动词原形 would/should/could/might＋动词原形 If my brother were here, everything would be all right. 要是我哥哥在这儿，一切都没问题了。(现在) If you had taken my advice, you wouldn't (couldn't) have failed in the exam. 如果你按照我的建议去做，你一定不会(不可能)考试不及格。(过去) If it were Sunday tomorrow, I should go to see my grandmother. 如果明天是星期天，我就去看望我奶奶。(将来) If it were to snow this evening, they would not go out. ＝If it snowed this evening, they would not go out. ＝If it should snow this evening, they would not go out. 如果今晚下雪，他们将不出去了。(将来) 考点延伸： (1)表示错综时间的虚拟语气 有时条件从句中的动作和主句中的动作发生的时间不一致，这时动词的形式要根据它所表示的时间加以调整。 If you had listened to the doctor, you would be all right now. 如果你当初听了医生的话，身体现在就好了。(从句动作指过去，主句动作指现在) (2)省略连词if 在书面语中，如果虚拟条件从句中有were, had或should，可以把if省略，把这几个词放到主语之前，构成倒装。 Should he come (If he should come), tell him to ring me up. 他要是来了，让他给我打个电话。 Were I you (If I were you), I would not do it. 我要是你，就不做这事。 (3)含蓄虚拟条件句 有时假设的情况并不用条件从句表示出来，而是通过介词短语来表示，也可以通过上下文或其他方式表现出来。 Without air (If there were no air), there would be no living things. 如果没有空气的话，就不会有生物了。 But for your help (If it hadn't been for your help), I couldn't have done it. 要是没有你的帮助，我就不可能完成这件事。 I was busy that day. Otherwise I would have gone there with them. (＝If I hadn't been busy that day, I would have gone there with them.) 我那天很忙，否则，我就和他们一起去那儿了。(如果我那天不忙的话，我就和他们一起去那儿了。) I would have finished the work, but I was ill. (＝If I hadn't been ill, I would have finished the work.) 我本来该完成这项工作的，但我生病了。(如果我没生病的话，我就会完成这项工作。) 考点二　虚拟语气的其他用法 1．虚拟语气在主语从句中的用法 在“It is important (strange, natural, necessary...) that...”这类句型里，that所引导的主语从句中的谓语动词常用“(should＋)动词原形”结构，表示某事是“重要”“奇怪”“自然”“必要”等意义。 It is important that every member (should) inform himself of these rules. 重要的是每个成员都应该知道这些规则。 2．虚拟语气在宾语从句中的用法 (1)在动词wish后的宾语从句中，表示与现在或过去的事实相反，或对将来的