语法系列9 虚拟语气.ppt

* 虚拟语气 虚拟语气表示动作或状态不是客观存在的事实，而是说话者的主观愿望、假设或推测。 一、虚拟语气在条件从句中的运用（非真实条件句） 在含有非真实条件句的复合句中，主句和从句的谓语动词都要用虚拟语气，主要有以下三种情况（见下一张幻灯片）： would (should, could, might) + have done had + 过去分词 与过去事实相反 would (should, could, might) + do 动词过去式 与现在事实相反 would (should, could, might) + do 动词过去式 should + 动词原形 were to + 动词原形 与将来事实可能相反 主句谓语动词 从句谓语动词 eg) If she knew English, she wouldn’t ask me for help. If I had known her number, I would have called her. If it were to rain tomorrow, they would stay at home. 虚拟语气在条件从句中的运用有三种特殊情况如下： 1.错综时间条件句 当条件从句与主句所表达的时间不一致时，主从句的谓语动词应做相应的调整。 eg) If they had started early in the morning, they would be here now. 2.含蓄条件句 有时假设的情况并不以条件从句的形式表现出来，而是隐藏在语境当中，或是通过某些词语（如without, otherwise, but for等）表现出来。 eg) But for your help, we wouldn’t have passed the test. = If you hadn’t helped us, we wouldn’t have passed the test. 3.if的省略和条件从句的倒装 在非真实条件从句中，如果谓语动词含有were, had（助动词）或should，可以省略if而把were, had或should提到主语前面构成倒装。 eg) Had I known her number, I would have called her. = If I had known her number, I would have called her. 二、“(should) + do型”虚拟语气 1. 在表示坚持、命令、建议、要求等的宾语从句或相关的名词性从句中，谓语动词用“(should) + do”。能用于这个句型的谓语动词主要有：一个坚持（insist），两个命令（order, command），三个建议（suggest, advise, recommend），四个要求（ask, demand, request, require）。 eg) They suggested that he (should) go there at once. It was suggested that he (should) go there at once. 2. 在“It is desired/important/necessary/strange/ natural/a pity… + that从句”中，从句中谓语动词用“(should) + do”。 eg) It’s a pity that he (should) be so careless. 三、“时态退步型”虚拟语气 1. 用于wish后的宾语从句中 eg) I wish you would go with us tomorrow. 2. 用于“It’s time + that从句”中 eg) It is high time that we took action. 3. 用于would rather后的宾语从句中 eg) I would rather I had not told her the news yesterday. 4. 用于as if / as though引导的方式状语从句中 eg) He talks as if / as though he knew all about it. 5. 用于if only引导的感叹句中 eg) If only I had taken your advice! 四、情态动词表示虚拟语气的用法 should have done = ought to have done 本来应该做而没有做 shouldn’t have done = oughtn’t to have done 本来不应该做而做了 could