before的用法归纳

1、before 的用法是很多的人都比较想要了解的，在众人的心中before 的用法是比较难的，我们都非常想要去了解before 的用法，但是又谈何容易呢?为了让大家更加快速的了解 before 的用法，下面我们就和教师一起去看看吧，希望对大家有所帮助。prep.在之前 ;先于，优于 ;当着 的面 ;与其 conj.在之前 ;在以前 ;比早些 ;与其 adv.先前，从前 ;在前，在前方before 一词含义广泛，是高考考查的热点词汇之一，但部分考生对该词的用法模糊不清。为了帮助大家掌握，现就对 before 的用法归纳如下：一、 before 用作连词1. before 用作连词时，意思是 “在之

2、前 ;还没来得及 就”。 强调主句或从句谓语动词表示的动作发生得过早或过快 ?例如：Before she could move, she heard a great noise, which grew to a terribleroar. 她还没来得及动弹， 就听见有很响的声音， 接着就成了可怕的隆隆轰鸣声。Before I could say a word, she had stormed out of the room. 不等我说一句话，她就冲出了房间。Don t count your chickens before they are hatched不.要高兴得过早。I must fini

3、sh my homework before I watch TV我.必须做完作业才能看电视。 It still took seven years before they finally got married. 过了七年他们才最终得以成婚。It will be only a few minutes before she comes back.她过几分钟就会回来。 He announced the ending of the meeting before I could get in a word. 没容得我插上一句话 ,他就宣布散会了 ?Someone called me up in the

4、middle of the night, but they hung up before I could answer the phone.有人半夜给我打电话 ,但我还未来得及接他就把电话挂断了 ?They had talked only a few minutes before they found they were quite different in opinion. 他们才谈了几分钟就发现他们的意见很不一致 ?注意： before 从句若是一个将来的动作，则用一般现在时代替一般将来时，如上句中的 comes。2. 用于 It + be + 时间段 + before.句型中，意思是 “

5、在之后才 ”。例如：It will be five years before I come back.我五年后才能回来。It was not long before the enemy was driven out of their country.不久之后，敌人就被赶走了。如果主句中用否定式，则表示“不多久 就”。It won t be long before they understand each other.他们不久就会互相了解的。3. 还有 “趁(还没有 ) ”之意。例如：They are thinking of buying the house before the prices

6、go up. 他们正在考虑趁房价未涨时把房子买下来。Do it before you forget it. 趁早动手，以免忘了。二、 before 用作介词before 用作介词时 , 可以指时间 “earlierthan 在之前 ”，也可以指位置“ in front of在之前 ”。例如：（1）表示时间，与after 相对。如：August comes before September. 8月份在 9 月份之前。There is nothing that has not been bitter before being ripe. 凡事在成熟前， 都是有苦味的。（2）表示顺序，与after

7、相对。如：Ladies before gentlemen女.士优先。（3）表示位置，与 behind 相对（相当于 in front of ）。如：Before Lucy is Lily莉.莉在露茜的前面。Dont put the cart before the horse.不要本末倒置。（4）表示 “在面前；与 面对面 ”。如：The poor little boy was brought before the headmaster. 那个可怜的小男孩被带到校长面前。He was brought before the judge. 他被带到法官面前。（5）表示 “宁可 而不愿 ”。如：Dea

8、th before dishonour. 宁死不辱。三、 before 用作副词（ 1）before 用作副词时，意思是 “at an earlier time / in the past以前 ”。表示 “以前；已经 ”，单独在句中作状语，句子常用完成时态。如：I have seen that film before.我以前看过那部电影。I ve seen the film Titanic before我.以前看过泰坦尼克这部电影。I have never seen such beautiful flowers before. 我以前从未见过如此美丽的鲜花。注意：区别于 ago: ago 用在

9、时间段之后，表示某个时间点，句子用一般过去时。如：I saw that film three years ago.我三年前看了那部电影。含有 ago 时间状语的直接引语变间接引语时，ago 应变为 before。如：He said to me,“ I saw that film three years ago.” He told me that he had seen that film three years before.(2)指空间或位置，表示 “在前面 ”。如：Look at the page before.看前面一页。四、4. 几个需要注意的地方（ 1）ever before,单独用

10、作状语，表示 “以前 ”；ever since, 单独用作状语，表示“自从那时以来 ”；ever after, 单独用作状语，表示 “以后；后来 ”。（ 2）before long,单独用作状语，表示 “不久以后 ”，其中 long 为名词，后面不接任何成分；可以用于各种时态。例如：Before long, he went to America. 不久，他就去了美国。 I hope to see you before long. 我希望不久后再见到你。long before：单独用作状语，表示“很久以前 ”，其中 before 为副词，其后不接任何成分；一般用在过去时或过去完成时的句子里。表示

11、 “在之前很久 ”，其中 before 用作介词或连词，后可接名词、动名词、代词或从句。 She said she had read the novel long before.她说她很久以前就读过这部小说。 That happened long before. 那件事发生在很久以前。（3）when/ while/ if/ unless/ once/ even though 等引导从句时， 如果从句主语和主句的主语相同或为it,并且从句谓语含有be 动词，则可以省略从句的主语和 be 动词部分，形成 “when / while / if / unless /once /even though

12、+V -ing 或V-ed 分词 ”结构；但是 before 和 after 则不用这一句式，二者后只接动名词或者完整的从句。 如：When (it is ) translated into English, the word means “newspaper”. 其中 it is 可省略 Before being operated on, he took some special medicine.其中 being operated on 为动名词的被动式， being 不可省略。before 可以用作连词 ,引导时间状语从句 ?它用法灵活 ?译法多变 ,是高考的一个重要考点 ?现对其用作连

13、词时的用法加以总结 ,希望对同学们有所帮助 ?1.【高考题例】 (加下划线的选项为正确答案) (2006 四川 ) Why didnt you tell him about the meeting?He rushed out of the room_I could say a word. (2003 北 京 ) He made a mistake, but then he corrected thesituation_it got worse.2. before 作“才”解时 ,强调从句谓语动词表示的动作发生得太慢或太晚 ?例如 :The bus driver almost knocked m

14、e down before he saw me. 那位公交车司机差一点把我撞倒 ,他才看到了我 ?The fire lasted about four hours before the firefighters were able to controlit. 大火持续了大约四个小时,消防队员才把火控制住 ?【高考题例】 (加下划线的选项为正确答案) (NMET 2004,) Several weeks had gone by_I realized the paintingwas missing. (2005 广东 ) The American Civil War lasted four yea

15、rs_the Northwon in the end.A. after B. when C. before D. then3. before 可译为 “趁”?“以免 ”?“以防 ”等?例如 :I ll do it now before I forget it趁.还没有忘 ,我现在就把这事做了 ?Wed better finish the work in time before the boss scolds us我.们最好按时完成这项工作 ,免得挨老板的骂 ?4. before 可译为 “(宁可 而)不愿 ”?例如 :Hed die before he apologizes to them他.

16、宁死也不向他们道歉 ?I d give up the plan before I turn to him for help我.宁可放弃计划也不会向他求助 ?5. 注意 “It + be +一段时间 + before 从句 ”中主句和从句的时态 ?该句式中 ,主句和从句的时态有两种情况 :如果主句用一般将来时 ,则从句用一般现在时 ,意为 “多长时间以后某事即将发生 ”;如果主句用过去时 ,从句也用过去时 ,意为 “多长时间后某事才发生 ”?【高考题例】 (加下划线的选项为正确答案) (2006 福建 ) How long do you think it will be_China sends

17、amanned spaceship to the moon?Perhaps two or three years.A. when B. until C. that D. before (2005 山东 ) It was some time_we realized the truth. A. when B. until C. since D. before练一练 :1. (2002 上 海 春 )It_long beforewe_the result oftheexperiment.A. will not be; will know B. is; will knowC. will not be;

18、 know D. is; know2. (2004 福建 ) Scientists say it may be five or six years_it is possibleto test this medicine on human patients.A. since B. after C. before D. when3. (2004 天津 ) It was evening _we reached the little townofWinchester.A. that B. until C. since D. before4. Why didnt you help the little boy?Oh, sorry. He had struggled to his feet _I ran over.A. before B. after C. until D. since5. Time passed quickly and three weeks went by _we knew it. A. before B. after C. when D. till6. She was such a proud person that she would die _she