1. C 理由，原因　 the cause of an event or situation; a fact, event, or statement that provides an explanation or excuse for sth
2. U 理性，理智　 the ability to think, understand, and form opinions or judgments that are based on facts

　analyze ～s　分析原因
　assign ～s　指出理由
　bear ～　听从道理，服理
　bring to ～　恢复理智
　cite a ～　引证理由
　cook up ～s　编造理由
　explain a ～　说明理由
　give a ～　说明原因
　have a ～　有理由
　hear ～　听从道理
　list five ～s　提到五点理由
　listen to ～　听从道理
　lose sb's ～　失去理智
　mention five ～s　列举五点理由
　see ～　看出理由，明白原因
　stand to ～　合乎情理
　state a ～　阐述理由
　use one's ～　用理智
　above ～　上述理由
　abundant ～　充分的理由
　apparent ～　明显的理由
　convincing ～　令人信服的理由
　every ～　充足的理由
　false ～　虚假的理由
　good ～　充足的理由
　logical ～　逻辑推理
　necessary ～　必要的理由
　obvious ～　明显的理由
　personal ～　个人理由
　political ～s　政治原因
　real ～　真正的原因
　sound ～　充分的理由，有根据的原因
　strong ～　强有力的原因
　sufficient ～　充分的理由
　the best ～s　最充分的理由
　the following ～s　下述理由
　understandable ～s　可以理解的原因
　urgent ～　紧迫的原因
　various ～s　种种原因
　against ～　背理
　by ～ of　由于…的原因，因为，为了
　by ～ of good planning　因为安排得好
　for a ～　由于…原因
　for no other ～ than that　只是因为…
　for some ～　由于某些原因
　for what ～　为什么
　in ～　合理，有道理，正当
　with ～　合乎情理
　without ～　不合乎情理
　～ against　反对…的理由
　～ behind　…真正的理由
　～ for　…的原因，赞成…的理由
　～ for changing the plan　改变计划的理由

　I can only guess the reason.　我只能猜测原因。
　We must inquire the reason.　我们必须问这理由。
　You should only stay away from school if you have a legitimate reason, such as illness.　你必须有正当理由，如生病，才可以不上学。
　She lost her reason in consequence of a violent emotion caused by a fire.　她因失火而过分伤心，以致失去理智。
　Only man has reason—animal does not.　只有人才有理智，而动物没有。
　His reason ruled his anger.　他凭理智抑制了愤怒。
　It is contrary to reason.　这不合情理。
　I have many reasons to think that he won't come.　我有很多理由认为他不会来。
　We have reason to believe that he was murdered.　我们有理由相信他被谋杀了。
　They have said the new product will be a success, and I see no reason to doubt it.　他们说过新产品会成功的，我看没有理由表示怀疑。
　We have good reason to believe that he is lying.　我们有充分的理由相信他在说谎。
　In view of her behaviour, you had every reason to be suspicious.　考虑到她的行为，你有充分的理由表示怀疑。
　The reason I didn't tell you was that I wanted it to be a surprise.　我没告诉你的原因是，我想让这件事使你感到意外的惊喜。
　The reason that he doesn't come is that he is ill.　他没有来的原因是他病了。
　The reason why she didn't get the job was that her English was not very good.　她没得到这个工作的原因是她的英语不是很好。
　The reason why he is late is that his car didn't come.　他迟到的原因是他的车子没来。
　Is there any particular reason why you can't come?　你有什么特殊的原因不能来?

 ♣ beyond all reason
　不合理的，不理智的　not reasonable; not acceptable
　Their demands are beyond all reason.　他们的要求完全是不合理的。
　Her outrageous words went beyond all reason.　她那些无礼的话全无道理。
 ♣ for reason
　由于…的原因　due to sth
　That child is always crying for no good reason.　那个孩子总是无缘无故地哭。
　Some people find themselves burst out crying for no reason at all.　有些人自己也不知道为什么，莫名其妙地就哭起来了。
　That girl burst into tears for no reason at all.　那个女孩莫名其妙地哭起来了。
　I have searched my mind for a reason, but can't find one.　我绞尽脑汁寻找理由，但是没找到。
　He resigned for reasons of health.　他由于健康原因而辞职。
　For some reason, he was neither surprised nor frightened.　由于某种原因他既不吃惊也不害怕。
 ♣ lose reason
　失去理智，发狂，发疯　drive sb mad
　Don't lose your reason however excited you are.　无论你多兴奋都不要丧失理智。
 ♣ reason for
　（某事）的理由　the cause of an event or situation
　The reason for the flood was that heavy rain.　水灾是那场大雨造成的。
　Give me your reason for doing it.　说说你做这件事的理由吧。
　There are a number of reasons for eating good food.　要吃好东西有许多理由。
　There is no reason for alarm.　没有理由惊慌。
　There must be some other reason for his refusing to help.　他拒绝帮忙，其中肯定还有别的原因。
　Our reason for coming to England is to learn.　我们来英格兰的目的是学习。
 ♣ see reason
　明白道理　understand reason
　He saw reason and gave up smoking.　他听从了劝告而不抽烟了。
 ♣ within reason
　合乎情理　within reasonable limits
　The bank will lend you as much as you need, within reason.　银行会合情合理尽量借给你所需的钱。
　He'll do anything for me within reason but he won't break the law.　在合理范围内他会为我做一切事情，但他不会违法。

 ♣ reason, cause, excuse, grounds
　参见cause条。
 ♣ 下面两个句子的意思相同：
　
 ♣ 下面两个句子的意思不同：
　

1. 他迟到的原因是因为下雨了。
　［误］ The reason why he was late was because it rained.
　［正］ The reason why he was late was that it rained.
　他迟到的原因是因为他没有搭上火车。
　［误］ The reason for his lateness is because he missed the train.
　［正］ The reason for his lateness is that he missed the train.
　［析］ “…的原因是因为…”，英文的正确表达是the reason... is that...，这里需要用that引导表语从句，而不能用because引导从句，以免意思重复。
2. 生病是她缺席的原因。
　［误］ Sickness is the reason of her absence.
　［正］ Sickness is the reason for her absence.
　［析］ “…的原因”是reason for (v-ing) sth，其中的for不能用of代替。
3. 他总是为迟到找理由。
　［误］ He always tried to make reasons for being late.
　［正］ He always tried to make excuses for being late.
　［析］ 如果所提的理由被认为不是真实的，或不能使人满意，通常用excuse而不用reason.

1. 引导the reason的定语从句，多数语法学家认为应是that，而章振邦和张道真两位先生却只给出why，实际上这两种都是可以的，许多语法书或辞书都有收录，故可放心使用。
2. 传统的语法规则认为the reason...is because...句型是错误的，应将because改为that. 但是，近些年来， the reason...is because...不仅在口语中，而且书面语也用得颇多，甚至得到了某些词典的认可。例如：
　The real reason people no longer wanted to be secretaries was because the pay was so low.　人们不想当秘书的真正原因是工资太低。不过为了稳妥些，还是少用because为好。

1. vi. & vt.推理；思考　 make use of one's reason; exercise the power of thought
2. vi. & vt.争辩　 say by way of argument

　～ point　讨论这一点
　～ deviously　不正当推理
　～ ineffectually　无效推理
　～ intelligently　明智地推断
　～ soundly　正确地推论，合理地思考
　～ away sb's nervousness　通过推理分析除去紧张不安感
　～ a person down　说服某人
　～ out a conclusion　推出一结论
　～ things out　讲道理
　～ out of　说服…不要做…
　～ sb out of going away　说服某人不要走
　～ out of sb's anxiety　劝某人不要担心
　～ sb out of the prejudice　说服某人消除偏见
　～ about a subject　就一个题目作推论
　～ against　反驳，进行反对…的辩论
　～ by syllogisms　用三段论法推论
　～ for　为维护…而辩论
　～ from the cause to the effect　从原因推论到结果
　～ from experience　根据经验推断
　～ sb into　说服某人（做）…
　～ sb into accepting the suggestion　说服某人接受建议
　～ sb into consent　说得某人表示同意
　～ sb into going away　说服某人离开
　～ on subject　研究课题
　～ with　同某人争辩
　～ with a person　同某人讲道理

　An idiot can't reason.　白痴不会分析问题。
　She can reason very clearly.　她能条理清楚地推理。
　A man can reason but an animal can't.　人能推理，而动物则不能。
　Do you think some animals can reason?　你认为某些动物会分析问题吗?
　His primary aim was to teach his students to reason.　他的首要目的是教学生逻辑思维。
　Copernicus reasoned that the earth revolved around the sun.　哥白尼推论说地球围绕太阳转。
　We reasoned that the terrorists would not negotiate unless we made some concessions.　我们推断，除非我们作出某些让步，恐怖分子不会同意进行谈判的。
　He reasoned that if we start at dawn, we could arrive before noon.　他争辩着说如果我们黎明出发，中午之前一定能到达。

 ♣ reason against　(v.+prep.)
　通过说理来反对…；据理反驳…　oppose sth, usually by thoughtful argument
　The lawyer reasoned against any changes being made in the law.　那位律师摆出道理，反对对法律的任何修改。
 ♣ reason from　(v.+prep.)
　根据…作出判断　make a judgment based on sth such as an idea
　The employer reasoned from his opinion of the workers and decided to increase their pay.　雇主根据其对工人的评价来决定提高他们的工资。
　I reasoned from his silence that he was unhappy.　我从他的沉默中判断他不高兴。
 ♣ reason into　(v.+prep.)
　以理劝说使之相信或使之做某事　persuade sb by thoughtful argument to believe sth or start doing sth
　See if you can reason the members into agreement with each other.　看看你是否能劝会员们取得一致的意见。
　You can easily reason yourself into even greater fear if you always think about the worst possibilities.　如果你总是考虑最坏的可能性，你就会使你自己更加害怕。
　Let me try to reason him into joining us.　让我想办法说服他加入到我们当中来。
　After some hours of discussion I managed to reason him into adopting a more conciliatory attitude.　经过几个小时讨论以后，我终于说服他采取比较和解的态度。
　This is something he can be reasoned into, given time.　如果有时间，这件事是可以劝他接受的。
　No one can be reasoned into accepting an idea that his feelings oppose.　无法说服任何人去接受自己感情上接受不了的观点。
 ♣ reason out　(v.+adv.)
　通过推理得出结论　find an answer to sth by thinking of all possible arguments
　〔说明〕 reason out通常不用于进行体。
　The solution is there if you care to reason it out.　只要你愿意把它琢磨透，解决问题的办法就不难找到。
　He reasoned the problem out and came to a conclusion.　他推想问题并得出结论。
　The workers have reasoned out that the real power is in their own hands.　工人们通过推理懂得真正的权力是在他们自己手中。
　We would not reason out where we were, because of the mist.　因为天有雾，我们当时不能推断出我们所在的位置。
 ♣ reason out of　(v.+adv.+prep.)
　以理说服，使其放弃　persuade sb against sth or doing sth by thoughtful argument
　How can you reason her out of fears that she has had all her life?　你怎样才能劝说她消除她一生中的恐惧呢?
　Can't you reason the boy out of such stupid behaviour?　你难道不能说服这孩子别做这种蠢事吗?
　Try to reason him out of that idea.　试一试劝他放弃那种念头。
　It is you who can reason him out of his prejudice.　只有你才能劝他消除偏见。
　Father must be reasoned out of driving home in such dangerous conditions.　必须以理来说服父亲不要在如此危险的情况下开车回家。
 ♣ reason with　(v.+prep.)
　跟…讲道理，以理规劝…　try to persuade usually sb, by fair argument
　You should reason with the child instead of just telling him to obey.　你应该同孩子讲清道理，不要只叫他听话。
　The teacher tried to reason with the boy but he refused to listen; children like that can often not be reasoned with.　老师想用道理来规劝这孩子，但是他不听，像他那样的孩子常常是不可理喻的。
　There's no reasoning with that woman.　那个女人简直不可理喻。
　There was no use reasoning with him.　跟他讲道理毫无效果。
　Reasoning with him was useless.　与他讲道理没有用。
　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。

 ♣ reason with, with reason
　这两个短语的用法和意思不同：reason with是动词+介词型短语，后接“人”，意思是“同…争辩”; with reason是介词+名词型短语，表示“合理，有理由”，在句中作状语。

　［同义词］ n. aim, argument, brain, cause, commonsense, excuse, explanation, ground, intelligence, judgement, mind, motive, object, objective, proof, purpose, sanity, understanding v. argue, assume, conclude, debate, deduce, discuss, dispute, gather, infer, justify, reflect, suppose, think
　［词源］　古法语reisun（计算，考虑）