/'ri:zn; `rizn/
n
1 [C, U] ~ (for sth/doing sth); ~ (to do sth); ~ (why.../that...) (fact put forward as or serving as the) cause of, motive for or justification for sth 原因; 动机; 理由
*for one/some reason or other 由于某种原因
* have adequate/sufficient reason for doing sth 有充分的[足够的]理由做某事
* all the more reason for doing/to do sth 做某事的更为充足的理由
* Give me your reasons for going/the reasons foryour going. 告诉我你去的动机.
* There is/We have (good) reason to believe that he is lying. 有[我们有]（充分的）理由认为他说谎.
* Is there any (particular) reason why you can't come? 你有什么（特殊的）原因不能来?
* The reason why I'm late is that/because I missed the bus. 我迟到的原因是没赶上公共汽车.
* My reason is that the cost will be too high. 我的理由是费用太高.
* We aren't going, for the simple reason that we can't afford it. 我们不去, 原因很简单
*我们负担不起.
* She complained, with reason (ie rightly), that she had been underpaid. 她抱怨她工资一直很低, 这也不无道理. =>Usage 见所附用法.
2 [U] power of the mind to think, understand, form opinions, etc 思考、理解、推想等的能力; 理性
*Only man has reason. 只有人类才有理性.
3 one's/sb's reason [sing] one's/sb's sanity 自己的[某人的]理智
*lose one's reason/senses, ie go mad 失去理智（即发疯）
* We feared for her reason, ie were afraid that she might go mad. 我们担心她可能失去理智.
4 [U] what is right or practical or possible; common sense or judgement 道理; 情理; 明智; 常识; 常理
*see/listen to/hear/be open to (ie be prepared to accept) reason 讲道理（服理）
* There's a good deal of reason in what you say. 你的话很有道理.
5 (idm 习语) be,yond/,past all `reason not reasonable or acceptable 不合道理的; 无法接受的
*Her outrageous remarks were/went beyond all reason. 她那些无礼的话全无道理. ,bring sb to `reason; ,make sb see `reason make sb stop acting foolishly, resisting uselessly, etc 使某人停止愚蠢的举动、无谓的抵抗等. by reason of sth (fml 文) because of sth 因为或由于某事物
*He was excused by reason of his age. 他因年高而获宥. for reasons/some reason best known to one`self (esp joc 尤作戏谑语) for reasons that are hard for others to understand or discover 出于惟本人才知道的原因
*For reasons best known to himself, he drinks tea from a beer glass. 谁都猜不透他为什么要用啤酒杯子喝茶. (do anything) in/within `reason sensible or reasonable 理智的; 合理的
*I'll do anything within reason to earn my living. 为了谋生, 只要是正当的事我什么事都做. lose all reason => lose. rhyme or reason => rhyme n. it/that ,stands to `reason it/that is obvious to everyone 这是人人都清楚的
*It stands to reason that nobody will work without pay. 做工作不能白做, 这是明摆着的事.

NOTE ON USAGE 用法
*A cause (of something) is what makes something happen *cause指事物发生的原因
*The police are investigating the cause of the explosion. 警方正在调查爆炸的原因.
* The causes of the First World War. 第一次世界大战的起因. Reason (for something) has a wider use. *reason一词用法较广. It can be the explanation that people give for why something is done 可用以解释做某事的原因或理由
*What was the reason for his resignation? ?
* She didn't give any reasons for leaving. 她未做任何解释就走了. Reason, justification and cause (for something) can indicate that the explanation is acceptable to people in general, or reasonable *reason、justification、cause三词均指用以解释的理由是一般人都可以接受的, 或曰reasonable
*The police had no reason to suspect him/no justification for suspecting him/no cause for suspicion (ie They didn't suspect him or shouldn't have suspected him). 警方是没有理由怀疑他的（即
*警方未怀疑他或不该怀疑他）. Ground is the formal, especially legal, justification for an action. *ground是用于较庄重场合的另一同义词, 尤用于法律文件中. It is commonly used in the plural 此词常用作复数
*Boredom is not a ground for divorce. 日久生厌不能成为离婚的理由.
* I left my job on medical grounds. 我由于健康原因而辞去了工作. A motive for doing something is a feeling or desire within people which makes them act *motive指想做某事的感觉或愿望
*He claimed that his motive for stealing was hunger. 他说他因为饿才去偷东西.
* The crime seemed to have been committed without
(a) motive. 这一罪案似乎并无作案动机.

/'ri:zn; `rizn/
v
1 (a) [I] use one's power to think, understand, form opinions, etc 思考; 理解; 推理
*man's ability to reason 人的思考能力.
(b) [Tf no passive 不用于被动语态] conclude or state as a step in this process 推论; 推断
*He reasoned that if we started at dawn, we would be there by noon. 他推断, 我们要是黎明出发, 中午就能到.
2 (phr v) reason sb into/out of sth persuade sb by argument to do/not to do sth 以理说服某人做[不做]某事
*reason sb out of his fears 劝说某人消除恐惧
* She was reasoned into a sensible course of action. 她听人劝而采取了理智的做法. reason sth out find an answer to (a problem, etc) by considering various possible solutions 考虑各种可能性以找出对（问题等）的解决办法
*The detective tried to reason out how the thief had escaped. 这个侦探反复琢磨想弄明白那个窃贼是怎样逃跑的. reason with sb argue in order to convince or persuade sb 为说服某人而与之理论
*I reasoned with her for hours about the danger, but she would not change her mind. 我跟她争辩了几个小时,想让她认识到危险性, 但她就是不听.
* There's no reasoning with that woman, ie She won't listen to arguments. 那个女人简直不可理喻.