含蓄虚拟条件句的用法是什么

题目

含蓄虚拟条件句的用法是什么
题目如下
I can’t thank you too much for your kindness because without your help I _________ have won the first prize in the speech contest.
A. can’t B. shouldn’t
C. might not D. couldn’t
答案选D 我疑问是B为什么不行 这个句子不是可以转化成I can’t thank you too much for your kindness because if you hadn't helped me, I _________ have won the first prize in the speech contest
这样不是可以填wouldn't、 couldn't 、shouldn't、 mightn't的吗 为什么这里就不能填shouldn't呢?

答案

这是含蓄条件句,与过去事实相反,主句用could,should would,might加have done,但是could,should would,might的本身含义还不一样,couldn't have won...(没有你的帮助,我就不可能在英语演讲中获得一等奖）,shouldn't含有不应该的意思.所以,这里不能用shoudn't,明白吗?

含蓄条件句的具体用法：
所谓含蓄虚拟条件句即指将条件从句隐藏在上下文一定的短语中的一类条件句,其主要用法及表现形式可归纳如下： 1. 将条件隐含在不定式短语中
I would write to her, but I don’t know her address. 我会给她写信的,就是不知道她的地址.(=If I knew her address, I would write to her. But…)
To have studied harder, you would have passed the examination. 你学习更用功些,你早就考及格了.(=If you had studied harder, you…)
2. 将条件隐含在分词短语中
Born in better times, he would have been a scholar. 如果出生在好时代,他早就成为学者了.(=If he had been born in better times, he would…
Failing this time, what would you do? 假若这次失败,那你怎么办?(=If you failed this time, what would…)
Walking alone in the dark, Mary would be terrified. 要一个人单独在黑暗中行走,玛丽会感到十分害怕.(If Mary walked alone in the dark, she…)
3. 将条件隐含在介词短语中
But for your help we couldn’t have succeeded in the experiment. 如果没有你的帮助,我们的实验是不会成功的.(=If it hadn’t been for your help, we…)
In different circumstances, I would have said yes. 在不同的情况下,我就会同意了.(=If circumstances had been different, I would…)
4. 将条件隐含在名词短语中
Any person who had behaved in that way would have been dismissed. 任何人这样做了都会被开除.(=If any person should behave in that way…, he would…)
A few hours earlier, and you would have seen the famous writer. 要是你早来几个小时,你就见到这位著名的作家了.(If you had come a few hours earlier, you…)
5. 将条件隐含在某些连词中
I didn’t know that he was a cheat, or else I wouldn’t have believed him. 我不知道他是个骗子,不然我也不会相信他了.(or else=if I had known he was a cheat))
I’m really very busy, otherwise I would certainly go there with you. 我真的是太忙了,不然我就会同你一道去了.(otherwise=if I were not so busy)
6. 将条件隐含在定语从句中
Anyone who had seen that painting might have taken it for a photo. 凡是看过那画的人,都可能把它看成是照片.(=If anyone had seen that painting…)
7. 将条件隐含在一定的上下文中
You might stay here forever. 你可以永远待在这儿.(=If you wanted to, you might…)
Don’t bother to read all these papers. It would take too long. 不要费事看所有这些文件了,那会花太多时间.(=…If you read all these papers, It would take too long