摘要： 常用连词的用法辨析 (1) while, when, as 这三个连词都可引导时间状语从句.但用法有所不同. 1) 当某事正在进行的时候.又发生了另一件事.While, when, as 都可用来引导表示“背景 的时间状语从句.例如: As/When/While I was walking down the street I noticed a police car.我沿着街道走时.注意到一辆警车. 2) 当两个长动作同时进行的时候.最常用的是while.例如: While mother was cooking lunch, I was doing my homework.当母亲做午饭时.我正在做作业. 3) 当两个动作都表示发展变化的情况时.最常用的是as.例如: As children get older, they become more and more interested in things around them.随着孩子的长大.他们越来越多对周围的事情感兴趣.www.zk5u.co 4) 当两个短动作同时发生时.或表示“一边-一边- 时.最常用as.例如: She looked behind from time to time as she went.她边走边不时地朝后面看. 5) 当从句的动作先于主句的动作时.通常用when.例如: When he finished his work, he took a short rest.当他完成工作后.他进行了短暂的休息. 6) 当从句是瞬间动作.主句是延续性动作时.通常用when.例如: When John arrived I was cooking lunch.当约翰到达时.我正在做饭. (2)as, because, since , for 这四个词都可表原因.但用法有区别. 1) 如果原因构成句子的最主要部分.一般用because.因此.because引导的从句往往放在句末.例如: I stayed at home because it rained.因为下雨.所以我呆在家里. ---Why aren’t you going? 为什么你不走? ---Because I don’t want to.因为我不想去. 2) 如果原因已被人们所知.或不如句子的其它部分重要.就用as或since.Since比as稍微正式一点.As和since 引导的从句一般放在句子的开头.例如: As he wasn’t ready, we left without him.由于他没有准备.我们没有带他. Since I have no money, I can’t buy any food.既然我没有钱.我不能卖任何食物. 3) for用来补充说明一种理由.因此.for引导的从句几乎可以放在括号里.For引导的句子不放在句子的开头.例如: I decided to stop and have lunch----for I was feeling quite hungry.我决定停下来.吃午饭.因我感觉很饿. (3)if, whether if和whether都可作“是否 讲.在引导宾与从句是一般可互换.例如: I wonder whether (if) you still study in that school.我想知道你是否还在那所学校学习. I don’t know whether (if) he likes that film.我不知道他是否喜欢这部电影. 在下列情况下.只能用whether,不能用if: 1) 引导主语从句时.例如: Whether he will come to the party is unknown. 他是否来参加聚会还不知道. 2) 引导表语从句时.例如: The question is whether I can pass the exam.问题是我能否通过考试. 3) 在不定式前.例如: I haven’t made up my mind whether to go there or not.我还没有决定是否去哪儿. (4)so-that, such...that 1) so-that中的so是个副词.其后只能跟形容词或副词.而such...that中的such是个形容词.后接名词或名词短语.例如: I’m so tired that I can’t walk any farther.我很累.因此不想再走了. It was such a hot day that he went swimming.如此热的天气.以至于他去游泳. 2) 如果在名词之前有many, much, little, few时.用so,不用such.例如: He has so little education that he is unable to get a job.他受到得教育很少以致于他找不到工作. (5)either-or-, neither-nor, not only-but also- 这三个连词词组都可连接两个并列成分.当它们连接两个并列主语时.谓语动词要随相邻的主语变化.例如: Either you or he is wrong. Neither he nor his children like fish.不但他不喜欢而且他的孩子也不喜欢鱼. Not only the teacher but also the students want to buy the book.不但老师而且学生想买这本书. (6)although, but 这两个连词不能用在同一个句子中.例如:我们不能说“Although he is over sixty, but he works as hard as others. 这个句子应改为:Although he is over sixty, he works as hard as others.或He is over sixty, but he works as hard as others.尽管他已是六十多岁.但他和其他工作一样努力. (7)because, so 这两个连词同样不能用在同一个句子中.例如:我们不能说“Because John was ill, so I took him to the doctor. 这个句子应改为Because John was ill, I took him to the doctor.或John was ill, so I took him to the doctor. 因为约翰病了.所以我带他看医生. ［辨析］ (1) because.as.since.for的用法: because表示原因的语气最强,常表示必然的因果关系,从句一般放在主句后面,另外,回答why的问句只能用because. as表示一般的因果关系,语气比because弱,说明比较明显的原因,它引导的从句可以放在句首也可以放在句尾.since表示对方已经知道.无需加以说明的原因或事实.for是并列连词,语气较弱,用来补充说明理由或提供一种解释.如: He is not at school today because he is seriously ill.(他今天没有上学因为他病得厉害) As all of you have got here, now, let’s go to the zoo.(既然大伙儿都到了我们就去动物园吧) I will ask Lin Tao to go with me since you are very busy.(既然你很忙我就叫林涛和我一起去吧) We must be off now for the match starts at 7:00.(我们得走了因为比赛在七点开始) (2)if.whether的区别:表示“是否 时,if和whether同义,引导宾语从句,另外,whether还可以引导主语从句.表语从句等名词性从句或者让步状语从句,而if还可以表示“如果 ,引导条件状语从句,(主句与从句遵循主将从现的原则).如: I don’t know if/whether he will arrive on time.(我不知道他是不是会按时到达) I will ring you up if he arrives on time.(如果他按时到达我会给你打电话的) [注意]下列情况只能用whether不能用if:①引导主语从句,②引导表语从句,③引导从句作介词宾语,④引导不定式短语,⑤引导让步状语从句,⑥在动词discuss之后,⑦在wonder / not sure之后,⑧在if与whether含义易混时.如: Whether it is a fine day next Sunday is still a question.(下个星期天是不是个好天还是个问题) Please ask him whether to go there with a raincoat or not.(请问一下带不带雨衣去那儿) Hainan is the place to be, whether it’s summer or winter.(海南是个该去的地方无论冬夏) Please let me know whether you need my help.(请告诉我你是否需要我的帮助)(如果换成if则还可能表示“如果你需要我的帮助请告知 ) (3)while.when.as的用法区别: while常表示一个较长的动作,它引导的从句动作与主句的动作是同时发生的.是平行的,when可以表示较短的动作也可以表示较长的动作,主句和从句的动作可以同时发生也可以先后发生,as与上两词同义,可替换while和when, 表示主句和从句的动作同时发生,常译为“一边--一边-- .如: Please do not trouble me while I am writing my homework.(我写作业时请不要打扰我) I’ll go home when I have finished my job. They were running quickly across the road when they heard the sound of a truck coming.(他们正快速地穿过马路忽然听到了卡车开来的声音) As we walked in the dark street, we sang songs and talked loudly.(当我们在黑洞洞的街上走路时我们高声地唱歌说话) (4)till/until与not-till/until的区别:前者表示一个延续性的动作,后者表示一个才开始的动作.如: I will stay here and watch the baby until you return.(我会呆在这里看着娃娃直到你回来)(stay这个动作一直进行到你return) They won’t go on working until they get what they think is reasonable.(他们要到获得了他们认为合理的东西时才会继续干下去的)www.zk5u.co 另外till与until基本可以互换,但是在句首时只能用until,不能用till. 如: Until the last minute of the match we kept playing.(我们坚持到比赛的最后一分钟) Not until he had finished his work did he go home. (5)though与although的区别: 两个词都表示“虽然 ,均不可以与but同时使用,但在句中可加still或yet连用.although“尽管.虽然 仅作连词,比较正式,一般可以换为though, though“虽然.尽管.即使 ,还可以与even连用,表示“即使.纵然 ,作副词时意思是“然而.不过 ,不能放在句首.如: He passed the exams although illness prevented him from going to classes.(尽管疾病使他无法上课但是他还是通过了考试)/ she won’t leave the TV set, www.zk5u.coeven though her husband is waiting for her for the supper.(她不愿离开电视机虽然丈夫在等她吃饭)/ It was a quiet party. I had a good time, though.(这是个不热闹的聚会尽管如此我还是玩得很开心) (6)prefer to-rather than-与prefer-to-的区别:prefer to-rather than-后面都是用动词原形,prefer-to-都是用动名词或名词.如: I prefer English to Japanese.(与日语相比我更喜欢英语) I prefer to learn English rather than learn Japanese. (与日语相比我更喜欢学英语) 并列句的分类:www.zk5u.co

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