谁知道英语中虚拟语气的用法?怎样判断句子是否用虚拟语气?

谁知道英语中虚拟语气的用法?怎样判断句子是否用虚拟语气?
谁知道英语中虚拟语气的用法?怎样判断句子是否用虚拟语气?

谁知道英语中虚拟语气的用法?怎样判断句子是否用虚拟语气?
虚拟语气的用法
一、虚拟语气条件从句
（一）与现在事实不相符合,主句动词would / should+动词原形,从句动词一般过去时（be可采用were形式）,如：
1. If I were you, I would phone the police. 如果我是你,我会打电话给警察的.
2. Would he pay all of us if he had the money? 他有钱了会给我们吗?
3. If it weren’t snowing, we wouldn’t stay in the house. 要是现在不下雪的话,我们就不会待在屋里.
（二）与过去事实不相符合,主句动词would / should have+过去分词,从句动词为过去完成时,如：
1. I would have died if they had given up searching. 如果他们放弃搜索,我会没命的.
2. If we had left a little later, we should have missed the train. 我们再晚点儿就赶不上火车了.
3. The shot would have killed me if I hadn’t had my mobile phone. 若不是有了移动电话,那颗子弹可能就击中了我.
4. If a better material had been used, the strength of the part would have been increased. 如果用了更好的材料,这个部分的力量就增加了.
5. Had the weather been good, the children could have gone out for a walk. 假如天气很好,孩子们都会出去散步. （省略连接词if,从句使用部分倒装语序.）
（三）与将来事实不相符合,主句动词would / should + 动词原形,从句动词should + v,或者动词过去式,或者were to + v,如：
1. If it were fine tomorrow, I should go to see my sister. 明天天好我就去看姐姐.
2. If he should go there tomorrow, she would meet him. 假如他明天去那里,她就会见到他.
3. If it were to snow tomorrow, I would go skiing. 如果明天下雪,我就去滑雪.
4. If I should have a chance to try it, I would do it in another way. 要是我有机会试一试,我会用另一种方法做的.
（四）主句与现在事实相反,从句与过去事实相反,主句谓语would / should + v, 从句谓语had + 过去分词；主句与将来事实相反,从句与过去事实相反,主句谓语would / should / were to do, 从句谓语had + 过去分词.如：
1. If you had taken the medicine last night, you would be much better now. 假如你昨晚吃药,现在就会好得多.
2. I wouldn’t have missed the flight last night if I were you. 如果我是你,就不会错过那航班.
3. If you had had the car repaired yesterday, we were to go there this afternoon. 如果你昨天修理一下车,我们今天下午就会到达那里.
4. They would be back home tomorrow evening if they had booked the tickets in advance. 如果他们提前订了车票,明晚就回到家.
（五）As if,as though,even if虚拟语气：
1. He looked as if he were an artist. 他看起来像一个艺术家.
2. He speaks English as if he had studied it in England. 他说起英语来就好像在英国学过一样.
3. Even if he were there,he could not solve the problem. 即使他在那里,也不能解决这个问题.
4. He talks as though he knew who she was. 他说气话来好像认识她一样.
（六）用于if only引导的感叹句中.例如:
1. If only I had taken his advice! 要是我听他的话就好了!
2. If only I were ten years younger now. 要是我现在年轻10岁就好了.
3. If only we had passed all the final exams! 要是我们期末考试都考过了就好了!
（七）一些介词词组或连词构成的句子或其他形式的句子也可以表达虚拟语气.常用的介词或连词有but（除外）, but for(除外,若不是), but that（若不是）, in that case（若那样的话）, or（不然）,without（没有）, otherwise（否则）等,是不是表达虚拟语气则要看句子的内容.如：
1. Without water there would not be life on the earth. 没有水,地球上就不会有生命.
2. But for electricity, there would be no modern industry. 要是没有电,就不会有现代工业.
3. We could have done the work better in that case. 要是那样的话,我们本可以把工作干得更好一些的.
4. But that you helped me a lot, I would have failed in getting good marks in English. 若不是你帮我很大的忙,我不会在英语上取得好成绩.
5. The teacher was lecturing then, otherwise, he would have played basketball with us. 老师当时在讲课,要不然他会更我们一起打篮球的.
6. He went away without a word. 他没说一句话就走掉了.（非虚拟语气）
二、虚拟语气宾语从句
虚拟语气有时也用在一些特殊动词所带的宾语从句中,表示希望、建议、命令、要求等.主句中常用的动词谓语有：insist, order, command, suggest, propose, advise, ask, demand, require, request, recommend等等,由于表达的建议、命令、要求等事情说话时还没有发生,这时宾语从句中从句的动词往往采用should/would+动词原形的方式,实际运用中往往省略should/would,只用动词原形.wish表达的愿望从句,表现为现在不能实现的愿望、过去不能实现的愿望和将来不能实现的愿望等.would rather(宁愿、但愿)是一种特殊用法.如：
1.The judge insisted that the accused man appear in person. 法官坚持让被告出席.
2. The doctor ordered that Ben stay in bed. 医生命令本卧床休息.
3. He suggested that his son be sent to the countryside. 他建议把儿子送到农村.
4. Our teacher asked that we hand in our homework today. 老师要求我们今天交作业.
5. I wish I knew the professor’s address. 我希望知道那个教授的地址. （表示现在不能实现的愿望,从句动词用一般过去时态.）
6. I wish I hadn’t spent so much money on lottery. 我真希望自己没在彩票上花那么多钱. （表示过去没有实现的愿望,从句动词用过去完成时.）
7. Peter wishes that he had studied law instead of literature when he was in college. 彼得希望上大学时学的是法律而不是文学. （表示过去没有实现的愿望,从句动词用过去完成时.）
8. She wishes she would learn all the English songs within a week. 她希望一周之内学会所有英文歌曲. (表示将来没有实现的愿望,从句动词用过去将来时.)
9. The board deemed it urgent that these files should be printed right away. 董事会认为,迫在眉睫的是马上把这些档案印出来.
10. I would rather
三、虚拟语气主语从句
在It is (was)important (necessary, desirable, imperative, advisable, incredible, urgent, possible, essential, natural, preferable, insistent, crucial, better, best, ridiculous, vital) that…能及It is (was) a pity (shame, wonder, must, suggestion, proposal, requirement, request, desire, order, recommendation) that….,It is (was)desired (arranged, decided, ordered, proposed, requested, recommended, suggested, settled) that…等句型的主语从句中,其谓语用“should+动词原形(其中should可以省略)”来构成虚拟语气.
1. It is important that we (should) speak politely. 我们说话要有礼貌,这是很重要的.
2. It is essential that these application forms be sent back as early as possible. 将这些申请表格尽快地反馈回来是很必要的.
3. It was a pity that you（should）be so careless. 你这么粗心大意真遗憾.
4. It’s desired that she come to teach us at least twice a week. 希望她每周至少来教我们两次.
5. It was my proposal that he be sent to further his study abroad. 我建议派他到国外进一步学习.
四、虚拟语气表语从句
作advise,order,suggestion,demand,plan,proposal,request等名词的表语从句和同位语从句,其谓语动词要用虚拟语气的结构“（should）+动词原形”.例如:
1. The plan is that another power station（should）be built in our city. 这个计划是在我们城市里再建造另一座发电站.
2. The general’s command was that the soldiers leave their fort and carry out more important task. 将军的命令是,战士撤离堡垒去执行更重要的任务.
3. Her demand is that all of us be present at the meeting. 她要求我们大家都要出席会议.
4. His proposal is that we have our lunch at the canteen. 他提议我们在食堂吃午饭.
五、虚拟语气定语从句
这种从句常用在“It is time that...”句型中,表示“该……”“是……时候了”.从句的谓语动词一般用“过去式或should/ought to+动词原形”的虚拟结构.例如:
1. It is （high） time we should go to bed. 该上床睡觉了.
2. It is time that we left for our hometown. 是我们离开家乡的时候了.
3. Do you think it is time you gave up smoking? 你认为是戒烟的时候了吗?
4. It is high time we had begun to prepare the experiement. 正是我们开始准备试验的时候.
六、虚拟语气同位语从句
使用名词表达愿望、建议、命令、要求等,而其后有从句补充说明愿望、建议、命令、要求等内容,构成虚拟语气同位语从句.如：
1.We all agreed to his suggestion that we（should）leave here at once. 我们都同意他的建议,立马离开这里.
2. We are all for the recommendation that John Strong be promoted to headmaster. 我们都赞同推荐约翰斯特朗为校长.
3. The workers raised the demand that their pay be increased to cope with the inflation. 工人们提出要求,上调工资以应付通货膨胀.
4. I offered the advice that we hike to the ancient castle the next day. 我建议我们第二天徒步去古城堡.
判断是真实条件句还是非真实条件句.只有在非真实条件句中才使用虚拟语气.通过句子意思,看假设的条件是否能够实现,能够实现是真实条件句,不能使用虚拟语气；假设的条件不能实现则是非真实条件句,要用虚拟语气.
判断这个假设是与哪个事实相反.通常有三种情况：①与过去事实相反.②与现在事实相反.③与将来事实可能相反.
在准确地判断了该句与哪一事实相反后,按虚拟语气的后退一步法处理从句谓语动词的时态.即：在非真实条件状语从句中,谓语动词按正常情况“后退一步”.也就是：
①与过去事实相反,在从句中用过去完成时形式表示.
②与现在事实相反,在从句中用过去一般时形式表示.
③与将来事实可能相反,在从句中用过去将来时形式表示.
主句中则用情态动词would, should, could 等加一个与从句一致的动词形式.
例：If I had come her yesterday, I would have seen him.
If I were a teacher, I would be strict with my students.
If it should snow tomorrow, they couldn’t go out.