Question

as，because和for的区别

Answer 1

原因状语从句一般由because, since, as, for引导?注意as,because,since和for的区别:
①如果原因是构成句子的最主要部分,一般用because。because引导的从句一般不放在句子的开头。例如:
I missed the train because I got up late.
注:对于以why开头的问句,一般只能用because引导的从句来回答。
②如果原因已为人们所知,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引导的从句一般放在句子的开头。例如:
As he was not well,I decided to go there without him.
Since this method doesn't work, let's try another.
③for表示所说的理由是一种补充说明,因此,for引导的从句可以放在括号里,而且for引导的从句一般不放在句子的开头。例如:
I decided to stop and have lunch, for I was feeling quite hungry.
because, for, since和as
这四个词作为连词，都有“因为”的意思，都可以用来作为一个动作或情况提供原因或理由，但它们在用法上有区别：
because是从属连词，接表示直接原因的从句，往往放在句末(有时也放在句首)，直接明白地说明因果关系。因此，在回答why的提问时或原句有just, only, not„but all等副词强调原因时必须用because.
for是并列连语。接表示间接原因的并列分句，所说的理由是一种补充。说明for引导的句子一般放在句尾。试比较：
He isn't here today because he is ill.因为他病了，所以他今天没有来。
He must be ill, for he isn't here.他今天没来，看来一定是生病了。
since和as是从属连词，说明的是已为人们所知和理由。since的语气比because弱，但比as强。since和as引导的从句一般放在句子的开头。
他因为忙，所以没来。
As I have a day off today, I'll write to you.
因为我今天有一天假，所以就给你写信。
此外，since也可以述说推断的理。如：
It must have rained, since the ground is wet.
一定下过雨，因为地是湿的.
because，since，as，for这些词在实际使用中都可以用做连词，当做“因为”、“由于”来讲，但要注意它们所表达意思的语气的顺序是be－cause，since，as，for，而且它们的具体用法还存在很大区别，我们千万不能混淆这四个词。
because表示“因为”，用来表示最直接的因果关系或是听话人所不知道的原因，它所表达的语气是这四个词中最为强烈的，它所引导的原因状语从句一般要放在主句之后。
还要注意两种情况也只能用because来回答：1、用why来提问的特殊疑问句的回答，只能用because；
2、在强调句中，只能用because。
例：1、He didn’t attend the meeting because he had too much work to do.
2、It is because it rained last week that they put off the match.
since在语气上仅次于be鄄cause，更加强调“既然”、“由于”，用来表示大家已然知道的事实。
例：Since we have no money,we can’t buy it.
as在语气上稍弱于since，不如since正式，而且经常用于口语。
例：As he wasn’t ready in time,we went without him.for是四个词当中表示“因为”、“由于”意思时语气最弱的一个，它实际只是对它前面的主句加以补充说明理由或推断原因，要用分号和前面的主句分开。

热身训练1、Why was he late for school?____he got up tool ate.
A、Because B、Since C、As D、For
2、"Is David at school today？""No,he is at home____he has a bad cold."
A、because B、since C、as D、for
3、It rained last night,___the ground is wet.
A.because B.since C.as D.for
key：1、A2、A3、D
Because 多用于表示直接原因, 而 for 可以表示原因又可以用于提出说明, 语气比 because 轻得多。 Because 引导的从句一般放在主句后, 有时也可放在主句前, 而 for 引导的句子只能放在后面。
because
[bi5kCz, bE5kCz, bi5kEz]
conj.
因为
John didn't attend the meeting because he was ill.
约翰没有出席会议, 因为他病了。
B-he is tired, he does not want to go with us.
因为他太疲劳所以他不想和我们一起去。 I criticized him, not because I hate him but because I love him.
我批评他不是因为我恨他而是因为我爱他。
because of
因为; 由于; 为了(I didn't go out because of rain. 因为下雨, 所以我没有出去。)【说明】在 reason is 的后面, 人们常用that 而不用 because 开头的从句。
for
[fE(r), fC:(r)]
prep.

给；为
a present for Mary
给玛丽的礼物
I've got a little present for your birthday.
我有一件小礼物送给你过生日。
I can do it for myself.
我自己能做这件事。
These investigations are not done for nothing.
这些调查工作自然不是白做的。
(2)
以„为目的地；开往；前往
We set off for London.
我们动身去伦敦。
(3)
在„时间
She's coming for Christmas.
她在圣诞节来。
(4)
代；替；代表
Red is for danger.
红色代表危险。
What do you want for a present?
你要什么样的东西作礼物?
(5)
为了
for existence
为了生存
"Did you come to Paris for the purpose of simple leisure, or for business purposes?" "你到巴黎来的目的纯粹是为了休闲,还是为了做生意?"
(6)
对于；关于
For him to forfeit his favourite hobby would be impossible.
要他放弃他所喜爱的业余爱好是不可能的。
I have no ear for music.
我对音乐外行。
For many of these families a college education was something new.
"对其中的许多家庭来说,大学教育是件新事物。"
(7)
因为
He's learning English for the fun of it.
他为了好玩才学习英语的。
for several reasons
因为种种原因
We bought this house with a much higher price than others just for its convenience. "我们买下这幢房子花的钱比其它房屋要贵得多,就是图的方便。"

仅管
For all his efforts, he didn't succeed.
他虽然竭尽全力还是没有成功。
"For all your explanations, I understand no better than before." "尽管你作了解释,我还是不懂。"
(9)
以„为价钱；付出
a pen for 50 pence 50 便士一枝笔
(10)
以„的价格，值
He paid 50 pence for the book.
他付了50便士买这本书。
(11)
经过（时间、距离）
We ran for two miles.
我们跑了两英里。
He stayed for a week.
他待了一周。
We haven't seen each other for ages.
我们好久没见面了。
(12)
用于for + 名词或代词 + to + 不定式动词的名词短语中
The bell rang for the lesson to begin.
开始上课的铃响了。
for example
例如
You can buy fruit here — oranges and bananas, for example.
你可以在这里买水果，例如买柑橘和香蕉。
"The government has reduced spending in several areas, for example in the construction of highways."
"政府已经在几个方面削减了开支,例如高速公路的建设。"
That's for you!
就是这样！
There's ... for you!
恰好相反
He just grabbed the money and left — There's gratitude for you!
他抓了钱就走，你可真会感激人！
since
KK: []
DJ: []
ad.(常用于现在完成时或过去完成时)
1. 此后;从那时到现在
She left school three years ago and has worked as a nurse ever since.
她三年前毕业,从那时起便一直当护士。
2. 之前,以前
prep.
1. (常用于现在完成时或过去完成时)自...以来,从...至今
I haven't heard from him since last year.
我自去年以来未曾收到过他的信。
conj.
1. (常用于现在完成时或过去完成时)自...以来,从...至今
It's been ten years since they married.
他们结婚到现在已经十年了。
She has been living a hard life since her husband died.
她自从丈夫死后,一直过着艰苦的生活。
2. 既然;因为,由于
He must have taken the book since it isn't here.
他一定是把书拿走了,因为书已不在这里了。
Since it is so hot, let's go swimming.
既然天气这么热,我们去游泳吧。
as
as 1
AHD:[2z] [„z ] 非重读时
D.J.[#z][*z ]非重读时
K.K.[#z][*z ]非重读时
adv.（副词）
(1)
To the same extent or degree; equally:
同等地，一样地：同一限度或程度地；同等地：
The child sang as sweetly as a nightingale.
这孩子歌唱得同夜莺般婉转
(2)
For instance:
例如：
large carnivores, as the bear or lion.
大的食肉动物，如熊或狮子
(3)
When taken into consideration in a specified relation or form:
被认为：当在特别的关系或形式中加以考虑时：
6/11
this definition as distinguished from the second one.
这个定义与第二个有区别
conj.（连接词）
(1)
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，常用作关联词后置于so 或 as ：
You are as sweet as sugar. The situation is not so bad as you suggest.
你甜如蜜。情形不如你说的那样糟
(2)
In the same manner or way that:
以同样方式，以同样方法：
Think as I think.
像我这样去想
(3)
At the same time that; while:
同时；当„时：
slipped on the ice as I ran home.
我跑回家时在冰上滑了一跤
(4)
For the reason that; because:
由于；因为：
went to bed early, as I was exhausted.
睡得早，因为我精疲力尽了
(5)
With the result that:
结果：
He was so foolish as to lie.
他太傻才会撒谎
(6)
Though:
尽管：
Great as the author was, he proved a bad model. Ridiculous as it seems, the tale is true. 这位作者尽管了不起，到头来却成了一个坏榜样。这个故事看似荒唐，却是真的
(7)
In accordance with which or with the way in which:
根据或按照这一方法：
The hotel is quite comfortable as such establishments go. The sun is hot, as everyone knows. 就设备而言，这个旅馆相当舒适。太阳非常热，这一点众所周知
(8)
Informal That:
【非正式用语】 相当于that：
I don't know as I can answer your question.
我不知道能否回答你的问题
pron.（代词）
(1)
That; which; who. Used after same or such :
7/11
that；which；who。用在same 或 such 后：
I received the same grade as you did.
我和你得分一样
(2) Chiefly Upper Southern U.S. Who, whom, which, or that:
【多用于美国中南部】 who，whom，which或that：
Those as want to can come with me.
想去的可以和我同去
prep.（介词）
(1)
In the role, capacity, or function of:
以„的身份，作为：充当角色、身份或功能的：
acting as a mediator.
充当调解人
(2)
In a manner similar to; the same as:
以相似的方式；如同：
On this issue they thought as one.
在这个问题上，他们意见一致
习惯用语
--------------------------------------------------------------------------------
as is【非正式用语】
Just the way it is, with no changes or modifications:
按现状：就用这种方式，不加改变或修饰：
bought the samovar as is from an antique dealer.
原封不动地从古董商那里买到这套俄国式茶具
as it were
In a manner of speaking; as if such were so.
以说的方式；似乎如此
as is
按现状（出售），概不保证（维修）
as it were
或者说
He is my best friend, my second self, as it were.
他是我最好的朋友，或者说，是第二个我。
as of right
依照法律
as yet
8/11

as if
好像，好似 She spoke to me as if she knew me.
她和我说话的神情，好像她早就认识我似的。
(= as though)
as long as
只要 You may borrow this book as long as you promise to give it back.
只要你答应归还，你就可以把这书借走。 (= so long as)
as of
自从；自„起
as of today
从今天起
(= as from)
as oppesed to
与„不同；与„相反
as though
好像，好似
as to 关于；至于
I don't know anything as to the others.
至于其他，我一无所知。
so As not to
以便不, 免得
so As to
这(那)样...以致
so long As
只要
so much As
连...都不
As above
如上, 同上
9/11
As against
与...比较; 比起...来
As... As any
不亚于任何一个; 不比别的差
As ... As anything
极为; 非常
As ... As ... can be
到了...的程度; 极其...
As ... As ever
(1)
永远; 依旧, 仍然
(2)
自古; 至今; 空前 (He is As brilliant a politician As ever lived. 他是古今最卓越的政治家。)
(3)
[与one 或you can 连用时]尽可能地; 越...越好(Be As quick As ever you can. 越快越好)
As for
至于; 就...方面说来
As from
从...时起(公文用语)
As if
好象...似的; 仿佛...一样
As though
好象...似的; 仿佛...一样
As is
[口]照原来的样子; 不予改变; 本来就是这样
As it is
事实上, 实际上; 照现在的样子
As they are
事实上, 实际上; 照现在的样子
As it were
仿佛, 好象, 可以说
As many (much) As
到...程度; 多达; 同量的
As of
在...时; 到...时为止; 从...时起
As to
(1)
谈到; 关于
(2)
至于
As well
(1)
倒不如, 还是...的好; 最好...还是(It will be As well to stop that young screamer. 但是最好还是让那个大哭大叫的孩子住声。)
(2)
同样; 也
As well As
也; 又
As well ... As not 反正都行; 都一个样(You may As well go there As not. 你去不去都行。)
As yet
[多用于否定句中]到现在为止; 到那时为止
A-you were!
【军】[口令]复原!

Answer 2

because, as, for, since这几个词都是表示“原因”的连词,语气由强至弱依次为：because→since→as→for;其中because, since, as均为从属连词,引导原因状语从句；而for 是并列连词,引导并列句.
1. because表示直接原因,它所指的原因通常是听话人所不知道的,其语气最强.常用来回答why的提问,一般放于主句之后,也可以单独存在.例如：
(1)I stayed at home because it rained. 因为下雨我呆在家里.
(2)Because Lingling was ill, she didn”t come to school. 玲玲因病,没有上学.
(3)�Why is she absent? 她为什么缺席?
�Because she is sick. 因为她病了.
此外,在强调句型中,只能用because.例如：
(4)It was because I missed the early bus that I was late for school. 我上学迟到是因为我没有赶上早班汽车.
2. since侧重主句,从句表示显然的或已为人所知的理由,常译为“因为”、“既然”,语气比because稍弱,通常置于句首,表示一种含有勉强语气的原因.例如：
(1)Since he asks you, you”ll tell him why. 他既然问你,那就告诉他为什么吧.
(2)Since everyone is here, let”s start. 既然大家都到齐了,我们就出发吧!
(3)Since I understood very little Japanese, I couldn”t follow the conversation. 我日语懂得不多,因而听不懂对话.
3. as是常用词,它表示的“原因”是双方已知的事实或显而易见的原因,或者理由不是很重要,含义与since相同,但语气更弱,没有since正式,常译为“由于,鉴于”.从句说明原因,主句说明结果,主从并重.例如：
(1)We all like her as she is kind. 我们都喜欢她,因为她善良.
(2)As I had a cold, I was absent from school. 因为我感冒了,所以没去上课.
(3)As Xiaowang was not ready, we went without him. 由于小王没有准备好,我们只好不带他去了.

4.
for用作连词时,与because相似,但它所表示的原因往往提供上文未交待过的情况.for不表示直接原因,表明附加或推断的理由,因此for被看作
等立连词,它所引导的分句只能放在句子后部(或单独成为一个句子),并且前后两个分句间的逻辑关系不一定是因果关系,其间用逗号隔开,且for不可置于句
首,for的这一用法常用在书面语中,较正式.例如：

(1)The days are short, for it is now December. 白天短了,因为现在已是十二月份.
(2)It must have rained, for the ground is wet. (从“地面潮湿”作出“下过雨”的推测,但地湿并不一定是下雨所致, for不可以换为because.)
(3)The ground is wet because it has rained. (“下雨”是“地上潮湿”的直接原因.)
前后两个分句间有一定的因果关系时(有时很难区分是直接原因,还是推测性原因),for与because可以互换使用.例如：
(4)I could not go, for / because I was ill. 我没能去,是因为我病了.
(5)He felt no fear, for / because he was a brave boy. 他没有害怕,因为他是个勇敢的男孩

Answer 3

　1．because “因为”，是连词。表示直接而明确的原因和理由，语气最强。because引导的从句一般不放在句子的开头。例如:

He didn’t come because he was ill.

注: 对于以why开头的问句,一般只能用because引导的从句来回答。

2．since表示原因时，语气比because弱，表示的原因是对方已知的，所说明的原因有时不是根本的或直接的原因，是附带的原因，一般把它译成“既然”。since比as稍微正式一些。since引导的从句一般放在主句之前。例如:

Since this method doesn't work, let's try another.

3. as用来表示原因时，只说明一般的因果关系，语气没有because重，它所引导的从句，可放在主句之前，也可放在主句之后。例如：

You needn’t go with me, as you are busy.

As I was afraid, I hid myself.

4．for表示所说的理由是一种补充说明,因此,for引导的从句可以放在括号里,而且for引导的从句一般不放在句子的开头。例如:

I decided to stop and have lunch, for I was feeling quite hungry.