ago和before的区别在哪里啊
1.ago表示“从现在起的若干时间以前”，意思是“距今……以前”，需和过去时或过去进行时连用。before泛指“从过去起的若干时间以前”，意思是“距过去某时……以前”“与其……（毋宁）”，常和完成时连用，尤其在间接引语中，如：I visited him three days ago, but he had gone to Shanghai a week before．我三天前去访问他，但他已与那时的一周前到上海去了。
His parents died ten years ago．他父母十年前都去世了。
He said that his parents had died ten years before．他说他父母亲十年前都去世了。
I have never been there before．我以前从来没有去过那里。
2.如果不具体表明多少时间以前，只用before不用ago，意为“从前、以前”。before仍以副词的形式置于被修饰语后，常与完成时候过去时连用。如：
Have you seen this film before?
He asked me whether I had been to the Great Wall before．
3.表示在某一点时间或事件以前时，只用before不用ago，这种用法是将before当作介词或连词使用。ago不具有这一功能。如：
They will come back before six o’clock．
It is hoped that this will be finished before the year 1995．希望这件工作将在1995年以前完成。
另外，before在句中的含义较多。不少句子中，before虽然引导的也是一个时间状语，但是译成汉语时却不必译为“在……以前”。
a.如果before引导的从句动作发生得晚或慢，可译成“……才”。这是主句主语或是名词、代词，或用it作形式主语．
He had almost knocked me down before he saw me．他几乎把我撞倒才看见我。
It will be hours before he arrives．要过几个钟头他才回到达。
You must sow before you can reap．有播种才能有收成。
b.如果强调从句动作发生之前，主句动作已发生，可译成“未……就”或“还没有……就”。
Before I could get in a word he had measured me．我还没有来得及插话，他就给我量号了尺寸。
Lu Ban built nine pavilions, but before he could finish the tenth, he heard a cock crowing．鲁班建了九个亭子，但他还没完成第十个就听到公鸡叫了起来。
c.有些句子中的before可译为“先……然后”、“先……再”。
Don’t count the chickens before they are hatched．不要乐观得太早。
Be pupil before you become a teacher．先做学生，再做先生。
有些句中的before还可译为“在……内”、“趁”、“没”。
They arrived before I expected．我没想到他们到得那么早。
Study hard before it is too late．趁早努力学习。
I had better go now before it is too late．最好我现在就走，免得太迟．
I will be through this book before three days have passed．我要在三天内看完这几本书．
before sb．knew it 一类习惯说法，常译为“不知不觉……就”、“还没弄清……就”、“不知怎么地……就”。
Time passed quickly and three months went by before Aqiao knew it．时间飞快的流失，阿巧不知不觉地在那里度过了三个月。
He fell from the tree before he knew it．他不知怎地一下就从树上掉了下来。
4.加强语气，表示“早已”的意思或使叙述显得更生动，ago也可以用于完成时。如：
I had thought that he had died at least twenty years ago．我本以为他至少二十年前就去世了。
In fact, I have long time ago known the secret．其实我早就知道那个秘密。
5.在表示对过去事情猜测的“情态动词＋have＋过去分词”或“动词的非谓语形式＋have＋过去分词”的结构中，ago 也可以和完成时连用。如：
The building is said to have been destroyed in a fire two years ago．据说那栋大楼在两年前的一场大火中已被烧毁。
The incident must taken place years ago．这是一定发生在好几年以前。
You can not have met him a moment ago．刚才你不可能遇见他。
He may have left an hour ago．他可能在一小时以前就走了。
Having read the article a week ago, I know it very well．一个星期以前我已读过这篇文章，我
三者均可表示“空地”、“空间”，区别如下：
1. 泛指一般意义的“空地”或“空间”，space 和 room 均可以用，但前者根据情况可用作可数或不可数名词，而后者通常只用作不可数名词。如：
The large table takes up too much space [room]. 这张大桌子太占地方了。
There isn't enough space [room] for all our luggage. 没有足够的地方可以放我们的行李。Here is an empty place, put the box here. 这里有个空地方，把箱子放在这里吧。
注：place 表示“太空”、“宇宙”，是不可数名词，而 room 表示“房间”，是可数名词。
He was staring into space. 他极目远眺。
This is one of the largest rooms here. 这是这里最大的房间之一。
2. place 表示“空地”，其含义通常比较具体，且往往指座位，有时与 seat 同义。如：
We'll try to get places (=seats) at the front of the hall. 我们要设法弄到大厅前面的座位。There are only two places (=seats) left for tonight. 今晚只剩两个座位。
A：Is there any room [space] in the boat? 船上有空处吗?
B：Yes, that place in the corner is empty. 在那边角落里还有个空位。
一、before与ago的区别 1.ago表示“从现在起的若干时间以前”，意思是“距今……以前”，需和过去时或过去进行时连用。before泛指“从过去起的若干时间以前”，意思是“距过去某时……以前”“与其……（毋宁）”，常和完成时连用，尤其在间接引语中，如：I visited him three days ago, but he had gone to Shanghai a week before．我三天前去访问他，但他已与那时的一周前到上海去了。 His parents died ten years ago．他父母十年前都去世了。 He said that his parents had died ten years before．他说他父母亲十年前都去世了。 I have never been there before．我以前从来没有去过那里。 2.如果不具体表明多少时间以前，只用before不用ago，意为“从前、以前”。before仍以副词的形式置于被修饰语后，常与完成时候过去时连用。如： Have you seen this film before? He asked me whether I had been to the Great Wall before． 3.表示在某一点时间或事件以前时，只用before不用ago，这种用法是将before当作介词或连词使用。ago不具有这一功能。如： They will come back before six o’clock． It is hoped that this will be finished before the year 1995．希望这件工作将在1995年以前完成。 另外，before在句中的含义较多。不少句子中，before虽然引导的也是一个时间状语，但是译成汉语时却不必译为“在……以前”。 a.如果before引导的从句动作发生得晚或慢，可译成“……才”。这是主句主语或是名词、代词，或用it作形式主语． He had almost knocked me down before he saw me．他几乎把我撞倒才看见我。 It will be hours before he arrives．要过几个钟头他才回到达。 You must sow before you can reap．有播种才能有收成。 b.如果强调从句动作发生之前，主句动作已发生，可译成“未……就”或“还没有……就”。
after用法小议 通常用于过去时、现在时（主将从现）或完成时态的句子中。 1. 1. 用作介词，与一段时间连用表示“在…之后”时，注意它与 in的区别：after表示以过去时间为起点的一段时间以后，且通常与过去时态连用；而in则表示以现在为起点的一段时间以后：He came back after two days. 他两天后就回来了。He will come back in two days. 他过两天就回来。但 after 若是与一点时间连用，则可与过去时态也可与将来时态连用：He came back after 4 o’clock. 他是四点钟以后回来的。 He will come back after next month. 他将在下个月以后回来。 eg. 2. I played computer games after I had finished my homework. 做完功课后，我玩电脑游戏。(从句的动作发生在主句的动作前，因此，主句用一般过去式，从句用过去完成时．) Before和after引导的时间状语从句中，由于before和after 本身的词义已经能够表明动作发生的先后，所以主句可以用一般时代替完成时，也可以用完成时。 I knew/had known her long before you knew her.我认识她早在你认识他之前。 After you finish/have finished all your homework,you can watch TV this evening.你完成所有的作业后，今晚可以看电视。
2. 用作连词引导时间状语从句时注意：若主句用将来时态 (或含有将来意味)，则时间状语从句要用一般现在时态 (表将来意义)表将来意义，而不能直接使用将来时态：他回来后我就走。正：I’ll leave after he comes back. 误：I’ll leave after he will come back. 3. 用作副词，表示“后来”、“ (一段时间)以后”，通常放在表示时间的副词之后：soon after 不久以后 two days after两天后 The plane was hijacked soon after it took off. Two days later he was gone. 4. 用于习语after all 终究，毕竟：I was right after all. 毕竟我是对的。After all, he’s only six years old. 毕竟，他才六岁。 before用法小结 请先看2005年广东省的一道高考题： The American Civil War lasted four years _______ the North won in the end. A. after B. before C. when D. then
详解ago与before的语法难点 1. before还是ago? 要说： I came to Manchester two weeks ago.I came to Manchester two weeks ago. 不要说： I came to Manchester before two weeks. Use past time + ago ago用于一般过去时，例如： 10 years ago, a long time ago, a few weeks ago, a couple of days ago Use before + action / event before用于动作或事件前，例如： before you left, before we start, before lunch 2. fall 还是reduce? These two words are the opposites of rise and raise: 它们是rise和raise的反义词： something falls (e.g. the price fell) somebody reduces something (e.g. the company reduced the price) You will probably use fall to describe numbers on a graph
or chart for IELTS Writing Task 1: 在雅思短作文中，你可以用fall来描述图表里的数字。 In 2008, the number of customers fell. (verb, past) 这里的fall是动词，过去时。 There was a sharp fall in Internet usage. (noun) 这里的fall是名词。 Reduce and reduction are probably more useful for Writing Task 2: reduce和reduction在长作文中更有用： We need to reduce the amount of pollution from exhaust fumes. (verb) reduce，动词。 Recycling leads to a reduction in waste. (noun) reduction，名词。 3. because还是because of? Compare these two sentences: 比较下列两个句子： I stayed at home because the weather was bad. I stayed at home because of the bad weather. The important difference is the use of the word was in the first sentence. After because, you need a subject and a verb (e.g. the weather was). After because of, we dont use a verb,
before的详细用法 Before 在英语中是一个比较常用的虚词，它既可作介词或副词用，也可作从属连词用。在近几年的高考试题中常常出现考查其从属连词用法的题目。其用法如下： 1.表示“在…..之前就…..”。 Mary had finished her homework before her mother returned. 2.表示“过了多久后才…….. ，动作进行到什么程度才……” They walked about 30 miles to the west before they saw a village . 3.表示“来不及；尚未…..就…” He ran off before I could stop him . 4.表示“刚…就…” I had hardly sat down before the bell rang. 5.表示“不知不觉就…..；还没弄清就……” Time passed quickly and three months went by before Aqiao knew it. 6.表示“宁愿…，决不…，与其…，毋宁….”常与will 或would 连用。 I would / will die before I surrender . 7.表示“否则；以免” I will write it down before I forget it . 8.用于句型“it was+时间段+ before …” 表示“过了多久才…” It was three days before he came back. . 9.用于句型“ it was not long +时间段+ before …” 意为“不久就….” It was not long before he sensed the danger of the position . 10. 用于句型“it will be(not )+时间段+ before….”表示“要过多久/ 不久…才…” It will be half a year before you graduate from this school .
ago 只作副词，必须与一段时间连用，表示以现在为起点一段时间之前。before既可以作副词也可以作连词。作副词时，可以单独使用;也可以和一段时间的词连用，表示的是已过去某个时间为起点一段时间之前。 ago 和before的区别 1、意思不同 ago 表示“从现在起若干时间以前”。 before 表示“从过去某时起若干时间以前”。 2、词性不同 ago只能作副词。 例句： She left England three days ago. 她三天前离开了英格兰。 before既可作副词又可作介词和连词。 例句： Please close the window before you leave. 离开前请关好窗户。(连词) 3、后接单词不同 ago常与动词一般过去式连用。 例句： His grandfather died two years ago. 他的外公两年前去世了。 before常与过去完成式连用。
例句： I had finished the work two days before. 两天前我就已经完成了工作。 ago的用法 1、用于一般过去时。 例句： A short while ago, my sister helped me to carry one of my old bookcases up the stairs. 片刻之前，我妹妹帮我把我的一个旧书柜抬上了楼。 2、所指的时间是从现在算起。 例句： It was stolen twenty years ago when Ted was a boy of fifteen. 那辆自行车是在20年前当泰德还是个15岁的小伙子时被偷去的。 before的用法 1、用于过去完成时 例句： A short time before, great trees had covered the countryside for miles around. 在那时不久之前，高大的树木覆盖着方圆数英里的地方。 2、它所指的时间不是从现在算起，而是从过去某一时刻算起，有时可以与previously 换用 例句： Last summer, I finally left the firm that I had joined eighteen years
before和ago都能表示在一段时间以前，但是二者的内涵和具体用法有明显的区别： 1. before表示从过去或将来某一时间算起多少时间以前，由于与这一时间状语连用的行为先发生在过去或将来某一时刻之前，因此往往出现在过去完成时态或将来完成时态中。例如： ①I called him up last night，but his mother told me he had left for Wuhan two days before. ②She said that she had married him five years before. 2.如果不具体表明多少时间以前，before意为"从前；以前"，表示从现在开始追溯到过去一段时间，或者主句的谓语动词表示的是经常、反复发生的行为，以副词的形式置于句末，可以用在现在完成时态中。例如： ①I have never been to Beijing before. ②Have you ever seen a tiger before? ③I often go over the lessons that I have learned a few days before. 注意：before前的时间状语如果是特定的，含义不一样。试比较： He said he had arrived here a day before. (一天前) He said he had arrived here the day before. (前一天) 3. ago指的是从现在起到过去时间的某一点的一段时间。这个时间状语常与一般过去时态或过去进行时态连用。例如： ①I graduated from the college twenty years ago. ②I was asked what I was doing a month ago. 4. 表示在某一时间点或事件以前时，只能用before，不用ago。因为这种用法是将before当作介词或连词使用。ago不具有这种功能。例如： ①He will come back before eleven o'clock.
Before的用法 一、用作介词 ⒈)指时间上早于，在……之前，如： We finished the work before noon. 中午以前我们完成了工作. ⒉)指位置在前面，如： We knelt down before Grandma's grave. 我们在奶奶的墓前跪下。 ⒊)指顺序或排列在之前，如： Your name comes before mine on the list. 名单上你的名字在我之前。 ⒋)在某人面前，如： She said it before the witness. 他是当着证人的面说的。 二、用作连词 其基本含义是“在……之前”，又可以根据不同语境灵活翻译成“才”、“还没来得及就……”、“趁……”、“就”等。具体用法如下： ⒈)与情态动词can/could连用 这时候从句虽为肯定形式，根据汉语表达习惯译成“还没来得及就”，如： Before I could get in a word，he had measured me. 我还没来得及插话他就为我量好了尺寸。Before she could move, she heard a loud noise, which grew to a terrible roar. 她还没来得及迈步，就听见一声巨响，接着就是可怕的隆隆轰鸣。 →The roof fell before he had time to dash into the room to save his baby. 他还没有来得及冲进房间救孩子，房顶就塌了。 ⒉)用于肯定句中强调主句所表达的时间，距离长，或花费的精力大，译成“才” We had sailed four days and four nights before we saw lands. 我们航行了四天四夜才看到陆地。 We waited a long time before the train arrived. 我们等了很长时间火车才到。 ⒊)用于否定句中，强调主句所表达的时间，距离短，或花费的精力小，译成“不到……就”如： We hadn't run a mile before he felt tired. 我们跑了还不到一英里他就累了。 ⒋)主句含有scarcely等半否定副词时可以译为“刚……就”，这时候主句应用过去完成时态，从句用过去时，还可以用when替代before如： We had scarcely reached the school before/when the bell rang. 我们刚到学校铃声就响了。 ⒌)有时还有“宁愿”的意思 I'd shoot myself before I apologized to him. 我宁死也不向他道歉。 ⒍)用于It+ be/takes+时间段+before句型 在这一句型中又可以根据主从句的时态分成两种情况。 若主句是一般将来时态，从句是一般现在时。若主句是肯定句意思是“要过多长时间才”；若主句是否定形式则翻译成“用不了多久就”。 It will be two weeks before everything returns to normal. 两周之后一切才能恢复正常。 It will be many years before the situation improves. 这种状况或许要过许多年才能得以改善。It won't be long before we meet again. 用不了多久我们就会再见面的。 这时若主句是一般过去时，从句也是一般过去时。若主句是肯定句翻译成“过了多久才……”或“动作进行到什么程度才……”，若主句是否定形式翻译成“没过多久就”。如：
“before”的用法及练习 高三课本第十五单元，INTER GATING SKILLS 和 WORKBOOK READING部分有如下的句子： ⒈The shop was successful，but it was about sixty years before people started to buy jeans for fashion as well as for work. ⒉However，it probably will not be long before the other mountainous areas of China such as Sichuan，Xinjiang and Yunnan are developed，and as more facilities become available，prices will almost certainly fall. 其中涉及到before的用法，下面就其用法进行总结。 一、可以用作介词 ⒈)指时间上早于，在……之前，如： She has lived here since before the war. 她从战前就一直在这儿住。 ⒉)指位置在前面，如： We knelt down before Grandma‘s grave. 我们在奶奶的墓前跪下。 ⒊)指顺序或排列在之前，如： Your name comes before mine on the list. 名单上你的名字在我之前。 ⒋)在某人面前，如： She said it before the witness. 他是当着证人的面说的。 二、作为连词
before和ago的区别 before和ago都能表示在一段时间以前，但是二者的内涵和具体用法有明显的区别： 1. before表示从过去或将来某一时间算起多少时间以前，由于与这一时间状语连用的行为先发生在过去或将来某一时刻之前，因此往往出现在过去完成时态或将来完成时态中。例如： ①I called him up last night，but his mother told me he had left for Wuhan two days before. ②She said that she had married him five years before. 2.如果不具体表明多少时间以前，before意为"从前；以前"，表示从现在开始追溯到过去一段时间，或者主句的谓语动词表示的是经常、反复发生的行为，以副词的形式置于句末，可以用在现在完成时态中。例如： ①I have never been to Beijing before. ②Have you ever seen a tiger before?
③I often go over the lessons that I have learned a few days before. 注意：before前的时间状语如果是特定的，含义不一样。试比较： He said he had arrived here a day before. (一天前) He said he had arrived here the day before. (前一天) 3. ago指的是从现在起到过去时间的某一点的一段时间。这个时间状语常与一般过去时态或过去进行时态连用。例如： ①I graduated from the college twenty years ago. ②I was asked what I was doing a month ago. 4. 表示在某一时间点或事件以前时，只能用before，不用ago。因为这种用法是将before当作介词或连词使用。ago不具有这种功能。例如：
before的用法 1．表示“在……之前”。说明两个时间或两个事件之间的先后关系。 1)They had got everything ready before I arrived．在我到达之前他们已经把一切都准备好了。 2)She didn’t understand me before I explained it to her．在我向她解释之前，她不理解我的意思。 3)The train had left before I arrived at the station．在我到达车站之前火车已开走了。2．表示“……才…… ”，强调从句的谓语动词所表达的时间、距离很长或花费的力量比较大。 1)The workers worked long hours for two weeks before everything returned to normal．工人们长时间地工作了两周，一切才恢复正常。 2)The big fire lasted four hours before the firemen brought it under contro1．大火持续了四个小时，消防队员才把它控制住。 3) We waited a long time before the train arrived．我们等了很长时间火车才到。 3．表示“还未来得及……就……”，强调主句谓语动词所表达的时间、距离很短或花费的精力比较小。 1)Before I could figure out what had happened，he forced me into the car．我还不知道发生了什么，他就强行把我推进了汽车。 2)He jumped into the water before I could stop him．我还没有来得及阻止他，他就跳进了水里。 3)Her father died before she was born．她尚未出世父亲就去世了。 4．表示“趁着……”。 1)We can set off early before it gets hot．我们可以趁着天不热早点出发。 2)You’d better write the phrases down before you forget them．趁着你还没有忘记，赶紧把这些词组写下来。 3)Please put them away before they are missing．趁着他们还没有丢，把它们收好吧。5．表示“一……就”、“刚刚……就”。与hardly．scarcely连用o 1)He had hardly gone to bed before(=when)the door bell rang．他刚刚睡下，门铃就响了。 2)She had scarcely got off the train before(=when)her daughter ran towards her．她刚一下车，女儿就跑了过来。 6．表示“不知不觉多少时间已经过去了”。 1)He was so absorbed in his work that four hours had passed before he knew it．他如此专注于工作，不知不觉四个小时就过去了。 2)Time passed quickly and three months went by before he knew it．时间飞快地流逝，他没感觉到三个月已过去了。 7．表示“宁可,宁愿”，相当于rather than。 1)I’d die b efore I apologized to them．我宁死也不向他们道歉。 2)1 would be poor before I got money in this way．我宁愿穷也不愿用这种方式挣钱。8．before常用于句型 “it was +段时间+before……”“过了(多长时间)才…… ”; “it will be……before…… ”“要用(多长时间)才……”; “it wasn’t……before……”“没过(多长时间)就……”; “it won’t be……before……”“用不了(多长时间)就会……”。 1)It was long before he came to help me．过了很久他才来帮我。 2)It wasn’t long before the fire was put out．不久火就给扑灭了。
ago和before的区别在哪里啊 1.ago表示“从现在起的若干时间以前”，意思是“距今……以前”，需和过去时或过去进行时连用。before泛指“从过去起的若干时间以前”，意思是“距过去某时……以前”“与其……（毋宁）”，常和完成时连用，尤其在间接引语中，如：I visited him three days ago, but he had gone to Shanghai a week before．我三天前去访问他，但他已与那时的一周前到上海去了。 His parents died ten years ago．他父母十年前都去世了。 He said that his parents had died ten years before．他说他父母亲十年前都去世了。 I have never been there before．我以前从来没有去过那里。 2.如果不具体表明多少时间以前，只用before不用ago，意为“从前、以前”。before仍以副词的形式置于被修饰语后，常与完成时候过去时连用。如： Have you seen this film before? He asked me whether I had been to the Great Wall before． 3.表示在某一点时间或事件以前时，只用before不用ago，这种用法是将before当作介词或连词使用。ago不具有这一功能。如： They will come back before six o’clock． It is hoped that this will be finished before the year 1995．希望这件工作将在1995年以前完成。 另外，before在句中的含义较多。不少句子中，before虽然引导的也是一个时间状语，但是译成汉语时却不必译为“在……以前”。 a.如果before引导的从句动作发生得晚或慢，可译成“……才”。这是主句主语或是名词、代词，或用it作形式主语． He had almost knocked me down before he saw me．他几乎把我撞倒才看见我。 It will be hours before he arrives．要过几个钟头他才回到达。 You must sow before you can reap．有播种才能有收成。 b.如果强调从句动作发生之前，主句动作已发生，可译成“未……就”或“还没有……就”。 Before I could get in a word he had measured me．我还没有来得及插话，他就给我量号了尺寸。 Lu Ban built nine pavilions, but before he could finish the tenth, he heard a cock crowing．鲁班建了九个亭子，但他还没完成第十个就听到公鸡叫了起来。 c.有些句子中的before可译为“先……然后”、“先……再”。 Don’t count the chickens before they are hatched．不要乐观得太早。
before long与long before的区别 1.before long的意思是“不久，很快”。（用于一般将来时或一般过去时） ①I'll be back before long. 不久我就回来。（一般将来时） ②Before long he got married. 不久他就结婚了。（一般过去时） 2.long before有两个用法： (1)老早，早就(单独使用，表示比过去某时早得多的时间。用于过去完成时) ①She had left long before. 她老早就离开了。（过去完成时） ②That had happened long before. 那事老早就发生了。（过去完成时） 【注】： ★long ago 表示“很久以前”，指的是从现在算起的很久以前，通常与一般过去时连用： I met him long ago. 我很久以前就认识他了。（一般过去时） ★not long ago 表示“不久前”，指的是从现在算起的不久前，与一般过去时连用： Not long ago a rare new species of bird-like dinosaur was discovered in Chaoyang County, Liaoning Province. 不久前，在辽宁省的朝阳县新发现了一种罕见的、形状像鸟一样的恐龙。 (2)在……的很久以前，在还没有……的很久以前。如： ①She had left long before his return [he returned]. （过去完成时） 在他回来的很久以前她就走了。 ②He had worked in the factory long before he got married. （过去完成时） 在他还没有结婚的很久以前他就在这家工厂工作了。 【注】：此时的主句谓语通常用过去完成时，但有时也可用一般过去时(因为before 已体现了动作的先后关系)。如： This happened long before you were born. 这事在你还没出生以前很久就发生了。
1．表示“在……之前”.说明两个时间或两个事件之间的先后关系. 1)They had got everything ready before I arrived． 在我到达之前他们已经把一切都准备好了. 2)She didn’t understand me before I explained it to her． 在我向她解释之前,她不理解我的意思. 3)The train had left before I arrived at the station． 在我到达车站之前火车已开走了. 2．表示“……才……”,强调从句的谓语动词所表达的时间、距离很长或花费的力量比较大. 1)The workers worked long hours for two weeks before everything returned to normal．工人们长时间地工作了两周,一切才恢复正常. 2)The big fire lasted four hours before the firemen brought it under contro1．大火持续了四个小时,消防队员才把它控制住. 3) We waited a long time before the train arrived．我们等了很长时间 火车才到. 3．表示“还未来得及……就……”,强调主句谓语动词所表达的时间、距离很短或花费的精力比较小. 1)Before I could figure out what had happened, he forced me into the car．我还不知道发生了什么,他就强行把我推进了汽车. 2)He jumped into the water before I could stop him． 我还没有来得及阻止他,他就跳进了水里. 3)Her father died before she was born．她尚未出世父亲就去世了. 4．表示“趁着……”. 1)We can set off early before it gets hot． 我们可以趁着天不热早点出发. 2)You’d better write the phrases down before you forget them． 趁着你还没有忘记,赶紧把这些词组写下来. 3)Please put them away before they are missing． 趁着他们还没有丢,把它们收好吧. 5．表示“一……就”、“刚刚……就”.与hardly．scarcely连用 1)He hadhardly gone to bed before(=when)the door bell rang． 他刚刚睡下,门铃就响了. 2）She had scarcely got off the train before(=when)her daughter ran towards her．她刚一下车,女儿就跑了过来. 6．表示“不知不觉多少时间已经过去了”. 1)He was so absorbed in his work that four hours had passed before he
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 terrible roar. 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 finish 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 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“在……之后才……”。例
before ago before和ago都能表示在一段时间以前，但是二者的内涵和具体用法有明显的区别： 1. before表示从过去或将来某一时间算起多少时间以前，由于与这一时间状语连用的行为先发生在过去或将来某一时刻之前，因此往往出现在过去完成时态或将来完成时态中。例如： ①I called him up last night，but his mother told me he had left for Wuhan two days before. ②She said that she had married him five years before. 2.如果不具体表明多少时间以前，before意为"从前；以前"，表示从现在开始追溯到过去一段时间，或者主句的谓语动词表示的是经常、反复发生的行为，以副词的形式置于句末，可以用在现在完成时态中。例如： ①I have never been to Beijing before. ②Have you ever seen a tiger before? ③I often go over the lessons that I have learned a few days before. 注意：before前的时间状语如果是特定的，含义不一样。试比较： He said he had arrived here a day before. (一天前) He said he had arrived here the day before. (前一天) 3. ago指的是从现在起到过去时间的某一点的一段时间。这个时间状语常与一般过去时态或过去进行时态连用。例如： ①I graduated from the college twenty years ago. ②I was asked what I was doing a month ago. 4. 表示在某一时间点或事件以前时，只能用before，不用ago。因为这种用法是将before当作介词或连词使用。ago不具有这种功能。例如： ①He will come back before eleven o'clock.
Before的用法: 一、before用作连词 1. before用作连词时,意思就是“在……之前;还没来得及……就”。例如: Before she could move, she heard a great noise, which grew to a terrible roar、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。 2. 用于It + be + 时间段+ before、、、句型中,意思就是“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、她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 go up、她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“earlier than在……之前”,也可以指位置“in front of在……之前”。例如: There is nothing that has not been bitter before being ripe、凡事在成熟前,都就是有苦味的。 Don’t put the cart before the horse、不要本末倒置。