asbecausesince和for的區(qū)別

1、原因狀語從句一般由because, since, as, for 弓I導(dǎo)注意 as,because,since 和 for 的區(qū)另U :如果原因是構(gòu)成句子的最主要部分，一般用because。because引導(dǎo)的從句一般不放在句子的開頭。例如：I missed the train because I got up late.注：對于以why開頭的問句，一般只能用because引導(dǎo)的從句來回答。如果原因已為人們所知，或不如句子的其余部分重要，就用as或since、since比as稍微正式一些。as和since引導(dǎo)的從句一般放在句子的開頭。例如 ：As he was not well,I decid

2、ed to go there without him.Since this method doesn't work, let's try another.for表示所說的理由是一種補(bǔ)充說明，因此,for引導(dǎo)的從句可以放在括號里，而且for引導(dǎo)的從句一般不放在句子的開頭。例如 ：I decided to stop and have lunch, for I was feeling quite hungry.because, for, since 和 as這四個(gè)詞作為連詞，都有“因?yàn)椤钡囊馑迹伎梢杂脕碜鳛橐粋€(gè)動(dòng)作或情況提供原因或理由，但它們 在用法上有區(qū)別：because是從屬連

3、詞，接表示直接原因的從句，往往放在句末（有時(shí)也放在句首），直接明白地說明因果關(guān)系。因此，在回答why的提問時(shí)或原句有just, only, not - but all等副詞強(qiáng)調(diào)原因時(shí)必須用because.for引導(dǎo)的句子一般放for是并列連語。接表示間接原因的并列分句，所說的理由是一種補(bǔ)充。說明在句尾。試比較:He isn't here today because he is ill.因?yàn)樗×?，所以他今天沒有來。He must be ill, for he isn't here.他今天沒來，看來一定是生病了。since和as是從屬連詞，說明的是已為人們所知和理由。since的

4、語氣比because弱，但比as強(qiáng)。since和as引導(dǎo)的從句一般放在句子的開頭。Since he was busy, he didn't come.他因?yàn)槊?，所以沒來。As I have a day off today, I'll write to you.因?yàn)槲医裉煊幸惶旒?，所以就給你寫信。此外，since也可以述說推斷的理。如：It must have rained, since the ground is wet.一定下過雨，因?yàn)榈厥菨竦?because , since , as, for這些詞在實(shí)際使用中都可以用做連詞，當(dāng)做“因?yàn)椤?、“由于”來講，但要 注意它們所表達(dá)

5、意思的語氣的順序是because, since , as, for ,而且它們的具體用法還存在很大區(qū)別，我們千萬不能混淆這四個(gè)詞。because表示“因?yàn)椤保脕肀硎咀钪苯拥囊蚬P(guān)系或是聽話人所不知道的原因，它所表達(dá)的語氣是 這四個(gè)詞中最為強(qiáng)烈的，它所引導(dǎo)的原因狀語從句一般要放在主句之后。還要注意兩種情況也只能用because來回答：1、用why來提問的特殊疑問句的回答， 只能用because ;2、在強(qiáng)調(diào)句中，只能用 because。例：1、Hedidn' tattend the meeting because hehad toomuchworkto do.2、 Itisbecaus

6、eit rainedlast week that theyput off thematch.since在語氣上僅次于 be鄴cause ,更加強(qiáng)調(diào)“既然”、“由于"，用來表示大家已然知道的事實(shí)。例：Sincewe haveno money,we can't buyit.as在語氣上稍弱于 since ,不如since正式，而且經(jīng)常用于口語。例：As he wasn' tready in time,we wentwithout是四個(gè)詞當(dāng)中表示"因?yàn)?quot;、"由于"意思時(shí)語氣最弱的一個(gè)，它實(shí)際只是對它前面的主句加以補(bǔ)充說明理由或推斷原因

7、，要用分號和前面 的主句分開。例：I asked hertostay to tea, for I had something to tell her.熱身訓(xùn)練 1、Why was he late for school he got up tool ate.A、BecauseB、SinceC As D For2、"Is David at school today""No,he is at home he has a bad cold.A、because B、since C asD> for3、It rained last night,the ground is

8、 wet.key ： 1、A2、Aa DBecause多用于表示直接原因，而for 可以表示原因又可以用于提出說明，語氣比because輕得多。Because引導(dǎo)的從句一般放在主句后，有時(shí)也可放在主句前，而for引導(dǎo)的句子只能放在后面。becausebi5kCz, bE5kCz, bi5kEzconj.因?yàn)镴ohn didn't attend the meeting because he was ill.約翰沒有出席會(huì)議，因?yàn)樗×?。B-he is tired, he does not want to go with us.因?yàn)樗谒运幌牒臀覀円黄鹑?。I criticized

9、him, not because I hate him but because I love him.我批評他不是因?yàn)槲液匏且驗(yàn)槲覑鬯?。because of因?yàn)椋挥捎?；為?（I didn't go out because of rain.因?yàn)橄掠?，所以我沒有出去。）【說明】在reason is的后面，人們常用that而不用because開頭的從句。forfE(r), fC:(r)prep.給；為a present for Mary給瑪麗的禮物I've got a little present for your birthday.我有一件小禮物送給你過生日。I can do

10、 it for myself.我自己能做這件事。These investigations are not done for nothing.這些調(diào)查工作自然不是白做的。(2)以一為目的地；開往；前往We set off for London.我們動(dòng)身去倫敦。在時(shí)間She's coming for Christmas.她在圣誕節(jié)來。(4)代；替；代表Red is for danger.紅色代表危險(xiǎn)。What do you want for a present你要什么樣的東西作禮物為了for existence為了生存"Did you come to Paris for the

11、purpose of simple leisure, or for business purposes""你到巴黎來的目的純粹是為了休閑，還是為了做生意”(6)對于；關(guān)于For him to forfeit his favourite hobby would be impossible.要他放棄他所喜愛的業(yè)余愛好是不可能的。I have no ear for music.我對音樂外行。For many of these families a college education was something new."對其中的許多家庭來說，大學(xué)教育是件新事物。&quo

12、t;因?yàn)镠e's learning English for the fun of it.他為了好玩才學(xué)習(xí)英語的。for several reasons因?yàn)榉N種原因We bought this house with a much higher price than others just for its convenience."我們買下這幢房子花的錢比其它房屋要貴得多，就是圖的方便?！?8)僅管For all his efforts, he didn't succeed.他雖然竭盡全力還是沒有成功。"For all your explanations, I

13、understand no better than before.""盡管你作了解釋，我還是不懂。"(9)以為價(jià)錢；付出a pen for 50 pence 50便士一枝筆(10)以的價(jià)格，值He paid 50 pence for the book.他付了 50便士買這本書。(11)經(jīng)過(時(shí)間、距離)一We ran for two miles.我們跑了兩英里。He stayed for a week.他待了一周。We haven't seen each other for ages.我們好久沒見面了。(12)用于for + 名詞或代詞+ to +不定式動(dòng)

14、詞的名詞短語中The bell rang for the lesson to begin.開始上課的鈴響了。for example例如You can buy fruit here oranges and bananas, for example.你可以在這里買水果，例如買柑橘和香蕉。"The government has reduced spending in several areas, for example in the construction of highways."”政府已經(jīng)在幾個(gè)方面削減了開支，例如高速公路的建設(shè)?！盩hat's for you!就是

15、這樣！There's . for you!恰好相反He just grabbed the money and left - There's gratitude for you!他抓了錢就走，你可真會(huì)感激人！sinceKK:DJ: 口ad.(常用于現(xiàn)在完成時(shí)或過去完成時(shí))1 .此后；從那時(shí)到現(xiàn)在She left school three years ago and has worked as a nurse ever since.她三年前畢業(yè)，從那時(shí)起便一直當(dāng)護(hù)士。2 .之前，以前prep.1 .（常用于現(xiàn)在完成時(shí)或過去完成時(shí)）自 以來，從 至今I haven't hea

16、rd from him since last year.我自去年以來未曾收到過他的信。conj.2 .（常用于現(xiàn)在完成時(shí)或過去完成時(shí)）自 以來，從 至今It's been ten years since they married.他們結(jié)婚到現(xiàn)在已經(jīng)十年了。She has been living a hard life since her husband died.她自從丈夫死后，一直過著艱苦的生活。3 .既然；因?yàn)?，由于He must have taken the book since it isn't here.他一定是把書拿走了，因?yàn)闀巡辉谶@里了。Since it is

17、so hot, let's go swimming.既然天氣這么熱，我們?nèi)ビ斡景?。as 1AHD:2zz 非重讀時(shí).#z*z 非重讀時(shí).#z*z 非重讀時(shí)adv.（副詞）To the same extent or degree; equally:同等地，一樣地：同一限度或程度地；同等地：The child sang as sweetly as a nightingale.這孩子歌唱得同夜鶯般婉轉(zhuǎn)（2）For instance:例如：large carnivores, as the bear or lion.大的食肉動(dòng)物，如熊或獅子When taken into consideratio

18、n in a specified relation or form:被認(rèn)為：當(dāng)在特別的關(guān)系或形式中加以考慮時(shí)：Jthis definition as distinguished from the second one.這個(gè)定義與第二個(gè)有區(qū)別conj.（連接詞）To the same degree or quantity that. Often used as a correlative after so or as : 像，如同：同等的程度或量，常用作關(guān)聯(lián)詞后置于so或as :You are as sweet as sugar. The situation is not so bad as y

19、ou suggest.你甜如蜜。情形不如你說的那樣糟(2)In the same manner or way that:以同樣方式，以同樣方法：Think as I think.像我這樣去想At the same time that; while:同時(shí)；當(dāng)時(shí)：slipped on the ice as I ran home.我跑回家時(shí)在冰上滑了 一跤(4)For the reason that; because:由于；因?yàn)椋簑ent to bed early, as I was exhausted.I睡得早，因?yàn)槲揖ＡΡM了With the result that:結(jié)果：He was so f

20、oolish as to lie.他太傻才會(huì)撒謊(6)Though:盡管：Great as the author was, he proved a bad model. Ridiculous as it seems, the tale is true.這位作者盡管了不起，到頭來卻成了一個(gè)壞榜樣。這個(gè)故事看似荒唐，卻是真的In accordance with which or with the way in which:根據(jù)或按照這一方法：The hotel is quite comfortable as such establishments go. The sun is hot, as ev

21、eryone knows.就設(shè)備而言，這個(gè)旅館相當(dāng)舒適。太陽非常熱，這一點(diǎn)眾所周知(8)Informal That:【非正式用語】相當(dāng)于that ：I don't know as I can answer your question.我不知道能否回答你的問題pron.(代詞)(1)That; which; who. Used after same or such :that ; which ; who。用在 same 或 such 后：I received the same grade as you did.我和你得分一樣(2)Chiefly Upper Southern . Who,

22、 whom, which, or that:【多用于美國中南部】who, whom which或that :Those as want to can come with me.想去的可以和我同去prep.（介詞）In the role, capacity, or function of:以一的身份，作為：充當(dāng)角色、身份或功能的:acting as a mediator.充當(dāng)調(diào)解人（2）In a manner similar to; the same as:以相似的方式；如同：On this issue they thought as one.在這個(gè)問題上，他們意見一致習(xí)慣用語as is【非正式

23、用語】Just the way it is, with no changes or modifications: 按現(xiàn)狀：就用這種方式，不加改變或修飾： bought the samovar as is from an antique dealer. 原封不動(dòng)地從古董商那里買到這套俄國式茶具as it wereIn a manner of speaking; as if such were so.以說的方式；似乎如此as is按現(xiàn)狀（出售），概不保證（維修）as it were或者說He is my best friend, my second self, as it were.他是我最好的朋

24、友，或者說，是第二個(gè)我。as of right依照法律as yet迄今，到目前為止as if好像，好似She spoke to me as if she knew me.她和我說話的神情，好像她早就認(rèn)識我似的。（=as though）as long as只要You may borrow this book as long as you promise to give it back.只要你答應(yīng)歸還，你就可以把這書借走。(=so long as)as of自從；自一起as of today從今天起(=as from)as oppesed to與不同；與相反as though好像，好似as to關(guān)于；至于I d