动词不定式作条件状语考点梳理(一)

动词不定式作条件状语考点梳理（一）
一、动词不定式作条件状语的历史传承
动词不定式作条件状语至少可以追溯到成书于1931年George O. Curme 著的Syntax，并且被中外的语法学家所认可，传承至今。

以下是动词不定式作条件状语的历史传承：
1. George O. Curme 著Syntax(1931年版) (汪璜译《英语句法》商务印书馆1989年8月第1版)(上册)P581:
“I was thinking of asking ￡30 for the month.”(for the use of the boat)—“The boat is not worth it to buy.”(=if one should buy it for that price)
《英语句法》(下册)P201:
I should be glad to go (= if I could go).
I should have been glad to go (=if I could have gone).
He would have been foolish to do it (=if he had done it).
2. R. W. ZANDVOORT 著A Handbook Of English Grammar (First published 1957)P10：In so-called “free-adjuncts”, the idea of purpose may be weakened, and even shade off into that of circumstance or condition.
To hear him talk, you’d think he knew all about the subject.
3. 李绍基编著的《英语非谓语动词》（译林出版社1981年12月第1版）P68：动词不定式短语有时也可用来表示一定条件，其产生的结果往往带有虚拟或主观推断的性质，因此句中的谓语动词前常用should, would, could, must等词。

例如：
To hear him talk, you would think he owned the whole world.(=If you should hear him
talk, …)
To look at him, you could hardly help laughing.
To listen to him, you should think that no problem whatever existed.
To judge by her reaction, she must deeply felt angry at your remarks.
You would be a fool to refuse this offer.
I should be sorry to see such a day.
4. 冯明仪编《英语非限定动词》(广东教育出版社1986年6月第1版)P46:
5.表示条件动词不定式表示条件，常见于虚拟语气中。

例如：
I should be glad for Mary to go. (= I should be glad if Mary went.)
You should have done better to have made up with them.(= You should have done better if you had made up with them)
5. 刘乐亭编著的《英语五难题》(北京出版社1989年2月第1版)P247: 3）作条件状语
To hear him speak English, one would take him for an English man.
6. 卢盛莽编著的《英语非谓语动词疑难详解》(辽宁大学出版社1989年12月第1版)P113:4）作条件状语。

不定式常用于句首，主句谓语动词多用于虚拟语气。

To listen to him, you should think that he has gone there. (笔者注：gone应为been)
To hear him talk, you should think he owned the whole world.
7. 李永生主编《实用英语语法》(光明日报出版社1990年10 月第1版)P169：
To hear him talk, you would think he owned the whole world.（条件）
8. L. G. Alexander著的Longman English Grammar《朗曼英语语法》(雷航等译，外语教学与研究出版社1991年1月第1版)P533：
To hear him talk, you’d think he was Prime Minister.(=if you could hear him talk)
9. 刘毅编著的《英语语法宝典》(北京师范大学出版社1993年12月第1版)P231:
表条件
You would make a great mistake to take his bribe.
(=You would make a great mistake if you took his bribe.)
I should be happy to be of any service to you.
(=If I am of any service to you, I should be happy.)
To hear him talk, you would take for a scholar.
(=If you heard him talk, you would take for a scholar. )
10. 何桂金编著《英语动词新编》(重庆大学出版社1996年7 月第1版)P247: 7)修饰整个句子表示条件。

例如：
I’ll thank you not to follow me. (= if you don’t follow me)
To look at him (If you looked at him), you could hardly help laughing.
11. 张道真编著的《英语语法大全》上册（外语教学与研究出版社1998年8月第1版）P711:
I should have been very pleased to have been present.
The servant would not have quitted to have been better treated.
12. 秦裕祥著的《英语语法专题研究》（湖南师范大学出版社1999年5月第1版）P180：不定式表示想象性条件，主要用于表示说话人的假设。

例如：
To hear him talk, you would think he owned the whole world.
A man would be blind not to see that.
To judge be her reaction, she must have deeply resented your remarks.
不定式表示的条件多为非真实条件，但有时也可见到不定式表示真实条件的的情况。

如它用于表示说话人主观设定的条件或与目的的意义相混杂的条件时即是如此。

You do an honest man wrong to call him a liar or a thief.
You have to be strong to lift a table like that.(笔者注：此句可参考18. )
To make other comfortable, you have to appear comfortable yourself.
13. 徐广联主编的《大学英语语法讲座与测试》(第二版)(华东理工大学出版社2000年)P569: 6) 表示条件动词不定式有时也可以表示条件。

一般置于句首，否定不定式多置于句尾。

例如：To look at her, you would think her a young woman, but she is in fact 47 years old. (= If you were to look at her)
One would be careless not to see the mistakes. (=if one should not see…)
You couldn’t do that to save your life.
I should have been sorry to have missed the chance.
14. 张满胜编著《英语语法新思维高级教程：驾驭语法》(世界知识出版社2002年4 月第1
版)P200: 3. 用作条件状语
You would be stupid not to ask for a raise.= You would be stupid if you don ‘t ask for a raise.
I would be very happy to be invited to the party.=… if I had been invited …. But I wasn’t invited.
15. 薄冰编著《高级英语语法》最新修订)(世界知识出版社2002年10 月第8次印刷) P295: 5)不定式偶尔亦可表让步或条件。

如：
To look at him you could hardly help laughing.
A man would be blind not to see that.
16. 贺立民编著《贺氏英语语法全书》(中山大学出版社2003年2月第1版)P764: 15.表示“条件”——相当于一个if-clause。

如：
To hear you sing, people might take you for a girl.= If people heard you sing, they might take you for a girl.
17. 王国栋编著的《大学英语深层语法》(清华大学出版社2005年1 月第1 版)P334：条件状语：通常置于句首，用逗号隔开。

如：
To hear him speak, you would think he owned the whole world. = If you should hear him speak, you would think he owned the whole world.
18. 张克礼编著《新英语语法》（第二版）（高等教育出版社2005年1月第2版）P221: (5)表
示条件，可取代条件状语从句：
I should be delighted to join you/if I could join you.
He would have been foolish to do it/if he had done it.
不定式分句有时把条件和其它语义结合在一起，如目的、理由等：
You must be strong to lift that weight.
= You must be strong if you are able to lift that weight.
= You must be strong in order to lift that weight.
= You must be strong because you are able to lift that weight.
19. 赵振才编著《英语常见问题解答大词典》(增订版)(世界图书西安出版公司2005年3月第1版)P684: 除了非真实条件状语从句之外，还有许多语言手段来表达非真实的情况。

动词不定式便是此种手段之一。

动词不定式用作条件状语时，它不是通过词汇手段（如，if, as long as, provided等），而是通过语法手段来表示条件关系的。

You would do well to write more distinctly.(事实是：你写得不清楚，动词不定式to write more distinctly提出与事实相反的条件)
In fact, the nation’s first settlers would have been very surprised to see how Americans celebrate Christmas today. (VOA)事实上，要是美国最早的定居者看到今天美国人庆祝圣诞节的盛况，会感到十分惊讶。

P685：【问】I would have given much to have been able to call off the whole thing.(复旦大学等校编《大学英语》精读4级一单元)
我们班很多同学将上面的句子理解为“为了能够取消这件事，我宁愿做出很大牺牲”。

不知这种理解是否正确？
【答】当看到主句中的would have given这一虚拟形式时，就应想到to have been able一定跟非真实条件有关。

完成体不定式（to have been able）更能显性地表示与过去事实相反的条件。

上面句子的意思是：要是那时我能够取消整个这件事的话，那我是多大的牺牲都愿做出来的。

20. [日] 绵贯阳等著《现代英语语法例解手册》(修订版))(申勇译科学出版社2006年2月第1版)P463:(5)表示条件。

也用于虚拟语气的句子结构。

To hear him talk, you would take him for a foreigner.
P539: You’d be crazy to expect that kind of thing to happen.(=If you were to expect that kind of thing to happen,…)
To hear him talk, you would think he was God Almighty. (=If you heard him talk, …)
21. 杨元兴主编《英语句型大全》(上海外语教育出版社2007年3月第1版)P1037：不定式短语也可表示真实条件，但不常见。

I’ll thank you not to follow me (=if you do not follow me).
To survive (=If we are to survive), we must have food.
P1044:不定式短语表示非真实条件。

It would be easier to do it this way (=if we were to do it this way).
To look at him (=If you were to look at him), you could hardly help laughing.
To hear him speak English (=If one were to hear him speak English), one would take him for an Englishman.
22. 章振邦主编的《新编高级英语语法》（上海外语教育出版社2012年12月第1版）P514：
To look at him (=If you were to look at him), you would think him a young man.
One would be a brute not to feel for the sufferings of the black people in South Africa (=if he should not feel for the sufferings of the black people in South Africa ).
23. 刘永科主编的《高中英语语法全解》（陕西人民出版社2013年3月第1版）P191：
You would be a fool to refuse his offer.
=If you should refuse his offer, you would be a fool.
24. 徐广联主编的《大学英语语法讲座与测试》(第5版)(华东理工大学出版社2014年1月第5版)P623: 6) 表示条件动词不定式可以表示条件，一般置于句首，否定不定式多置于句尾。

不定式表示条件时，句中谓语常含有will, shall, should, would, can, must等。

例如：
To look at her, you would think her a young woman, but she is in fact 47 years old.(= If you were to look at her)
One would be careless not to see the mistake.(= if one should not see)
How can you catch the train to star so late?
You couldn’t do that to save your life?
You do an honest man wrong to call him a liar.
You will do better to get her support.(=if you get her support)
To be successful, one must do one’s best.
I should be very happy to be of service to you.
One will get into trouble to do such a thing.
To be a masterpiece, the book needs revising again and again.
You will regret one day for your son to marry her.
I should have been sorry to have missed the chance.
She would have been astonished to have received a letter from a stranger.。