
1.if引导的非真实性条件句(虚拟条件句).
Eg.If you had come a few minutes earlier, you would have met him.(与过去事实相反) 要是你早来几分钟的话,你就能见到他了。
If it were(should be/were to be) sunny tomorrow, I would come to see you.(与将来事实相反) 明天要是天气好的话,我来看你。
注意:与将来事实相反的虚拟条件句中,通常有表将来的时间状语。同时,条件从句的谓语形式were(did)/should do/were to do所假设的可能性程度逐渐变小。
If I were you, I would go now. (与现在事实相反,事实上我不可能是你)
我要是你的话,我现在就走。
虚拟条件句中,表示与事实相反的条件,分为以下三种情况(以do为例):
| 表与事实情况相反 | 条件从句的谓语形式 | 主句的谓语形式 |
| 与现在事实相反 | 过去式(did) (be常用were) | Would/could/might/should+动词原形(do) |
| 与过去事实相反 | 过去完成时(had down) | Would/could/might/should+have done |
| 与将来事实相反 | 过去式(did)(were) Should+do Were to do | Would/could/might/should+动词原形(do) |
Eg.If I were to meet him tomorrow,I should ask him about it.
Were I to meet him tomorrow, I should ask him about it.
If he should fail in the experiment this time, he would try again.
Should he fail in the experiment this time, he would try again.
If you had come a few minutes earlier, you would have met him.
Had you come a few minutes earlier, you would have met him.
3.在宾语从句中的虚拟语气:
1)在以下这些词后面接的宾语从句中需要用虚拟语气:
表示愿望(wish),后接宾从中的虚拟语气有三种情况:
Eg.I wish I were 30 years younger. 但愿自己能年轻30岁。
表示现在不可能实现的愿望,从句谓语动词用过去时态(did/were)
Eg.He wished he hadn’t done it.他想要是他没这样做该多好。
表示过去不可能实现的愿望从句谓语动词用过去完成时(have done)
Eg.I wish that you would get a good job.我希望你能找到个好工作。
表示对将来的虚拟,从句谓语动词用情态动词would/could+do
表示建议(suggest/advice/propose/recommend/urge)
要求(demand/request/require/insist)
命令(order/command))等引导的宾从中,常用should+do型虚拟语气,should可省略。
Eg.The doctor suggested that he (should) try to lose weight.
They urged that the school library(should)be kept open during the vacation.
He insisted that all of us (should) be there on time by any means.他坚持要我们想尽办法按时去那儿。
He ordered that the students (should) wash the clothes every week by themseves. 他要求学生每周都要自己洗衣服
注:suggest若表示“表明、暗示”时,则用陈述语气。
Eg.Her smill suggested that she agreed with us.
Insist表示“坚持要求”时引导的宾从中用虚拟语气,表示“坚持说,坚称”时用陈述语气,表示事实。
Eg.He insisted that he was right. 他坚称他是对的。
4.主句的主语常是表示说话人愿望(wish/desire)、建议(suggestion/advice)、要求(requirement/demand)、命令(order/command)等的名词,表语从句的谓语动词用(should)+do.
Eg.The suggested is that you (should) be there on time.
5.同位语从句的先行词常是表示说话人的愿望、建议、要求、命令等的名词。
Eg.The suggestion that students (should) learn something practical is worth considering.
Do you know the order that you (should) take the task.
6.在句型“it is important/necessary/strange/natural+that从句”中,that后面的从句谓语动词用should+do
Eg.It’s natural that she should do so. 他这样做事很自然地。
It’s important that we should take good care of the patient.重要的是我们要照顾好病人。
7.在as if/though从句中常用虚拟形式,即表示与现在事实相反时,用过去式;与过去事实相反时,用过去完成式(had done).
1)as if连接表语从句时,
eg. She looked as if she were made of ice.她看起来似乎是冰做的。
He looked as if he hadn’t slept for two days.
2)as if 连接方式状语从句时,
eg.She looked after the boy as if he were her own son.
He speaks to us as if he had been there.他给我们讲的好像他去过那儿。
8.if only...意为“若是......那该多好啊;真希望;只要,只要……就好”
若表示现在的情况是谓动词应用过去式;若是过去的情况谓动词用过去完成时态。
Eg.If only I had arrived in time!
If only she didn’t drive so fast.
9.It’s (high/right) time that...(从句中谓动词用过去时或should+do)
Eg.It’s time that you left/should leave here.
10.在would (had) rather(宁愿)引导的宾语从句中
当从句表示现在或将来的时间时,谓语动词要用一般过去时;表示过去的时间时,谓语动词要用过去完成时。
Eg.I would rather he/you came tomorrow than today.
11.以下介词短语,如:but for(要不是),without,otherwise(否则)等表示含蓄的条件,这时主句要用虚拟语气。
Eg.Without your help, we would not have made such rapid progress.
