英语语法同位语从句,宾语从句,主语从句,表语从句的具体区别,（要各带例句的）

英语语法
同位语从句,宾语从句,主语从句,表语从句的具体区别,（要各带例句的）

同位语,宾语,主语和表语从句都使名词性从句以下为区别.
主语从句
主语从句(Subject Clause)
主语从句 定义:在句子中担当主语的是一个从句,这个从句就叫做主语从句.
主语从句是在复合句中充当主语的从句,通常放在主句谓语动词之前或由形式主语it代替,而本身放在句子末尾.
1. It 作形式主语和it引导强调句的比较
It 作形式主语代替主语从句,主要是为了平衡句子结构,主语从句的连接词没有变化.而it引导的强调句则是对句子某一部分进行强调,无论强调的是什么成分,都可用连词that.被强调部分指人是也可用who/whom.例如：
It is a pity that you didn’t go to see the film.
2. 用it 作形式主语的结构
(1) It is ＋名词＋从句
It is a fact that … 事实是…
It is an honor that …非常荣幸
It is common knowledge that …是常识
(2) it is ＋形容词＋从句
It is natural that… 很自然…
It is strange that… 奇怪的是…
(3) it ＋不及物动词＋从句
It seems that… 似乎…
It happened that… 碰巧…
(4) it is＋过去分词＋从句
It is reported that… 据报道…
It has been proved that… 已证实…
3. 主语从句不可位于句首的五种情况
(1) if 引导的主语从句不可居于复合句句首.
(2) It is said , (reported) …结构中的主语从句不可提前.例如：
It is said that President Jingo will visit our school next week.
(3) It happens…, It occurs… 结构中的主语从句不可提前.例如：
It occurred to him that he failed in the examination.
(4) It doesn’t matter how/whether …结构中的主语从句不可提前.例如：
It doesn’t matter whether he is wrong or not.
(5) 含主语从句的复合句是疑问句时,主语从句不可提前.例如：
Is it likely that it will rain in the evening?
4. What 与that 在引导主语从句时的区别
What 引导主语从句时在从句中充当句子成分,如主语．宾语．表语,而that 则不然.例如：
What you said yesterday is right.
二：宾语从句的几个特征：1、引导词：what\which\whose\when\whether\if\where
2语序：宾语从句必须是用陈述语句.
如：I think that you must work harder.
宾语从句的引导词、连接词的区别、否定转移等现象.
(1)表达时间的几个句型：一般用when或者是what time：
What time will the train leave?
由于时刻都是固定的,也可以用一般现在时代替一般将来时：
What time does the train leave?
(2)时间的表达方式：8：19(nineteen past eight),7:57(three to eight),在时间的中间也可以加上分的单词(minutes)
(3)had better +动词原型.意思是提要求,建议.但是上下级不能用这种方式,因为语气太重：
You had better give up smoking .
(4)sb leave sth +地点
I left my book in my classroom yesterday.
(5)may I have your name(address\age)?一般询问对方的年龄、名字等,不要习惯以前的问法,这样很不礼貌,而是要采访上面的问法.以前的习惯是：how old are you? \what's your name?
(6)修饰名词的代词次序：限-描-大-形---年---颜----籍----物--------类+名词：
this is a bridge.
This is a beautiful bridge
表语从句
表语从句
一 定义：
A 表语从句就是用一个句子作为表语.说明主语是什么或者怎么[1]样,由名词、形容词或相当于名词或形容词的词或短语充当,和连系动词一起构成谓语.
The problem is puzzling.
这问题令人困惑
主语 连系动词 形容词作表语
The problem is when we can get a pay rise.
问题是,当我们可以得到加薪.
主语 连系动词 一个句子作表语---表语从句
B 连接表语从句的连接词有：that, what, who, when, where, which, why,
whether,how.
He has become a teacher.
他已经成为一名教师.
He has become what he wanted to be ten years ago.
他已经成为了他10年前想成为的.
She has remained there for an hour.
她曾在那里停留了一个小时.
She has remained where I stood yesterday for an hour.
她一直在我昨天站的地方站了一个小时.
His suggestion is good.
他的建议是好的.
His suggestion is that we should stay calm.
他的建议是,我们应该保持冷静.
The question is confusing.
这个问题令人困惑.
The question is when he can arrive at the hotel.
问题是,他什么时候可以到达酒店.
who will travel with me to Beijing tomorrow.谁与我明天将前往北京.
why he cried yesterday.
昨天他为什么哭.
how I can persuade her to join us in the party.
我怎么能说服她加入我们的派对.
whether the enemy is marching towards us.
是否敌人正向我们行进.
二 注意：
A 表语从句一定要用陈述语序.
False: The question is when can he arrive at the hotel.
Right: The question is when he can arrive at the hotel.
B 不可以用if,而用whether 连接表语从句(as if 例外）.
引导宾语从句时可以互换if/whether 位于介词后要用whether
位于句首时要用whether
引导表语从句,主语从句,同位语从句时要用whether
False: The question is if the enemy is marching towards us.
Right: The question is whether the enemy is marching towards us.
Right: It looked as if he had understood this question.
C 不像宾语从句,在有表语从句的复合句中,主句时态和从句时态可以不一致.
Right: The question is who will travel with me to Beijing tomorrow.
Right: The question is why he cried yesterday.
D that在表语从句中不可以省掉.
表语从句的基本用法
表语从句只能置于主句之后,而主句的动词只能是联系动词.
名词性从句在be等系动词后作表语时被称为表语从句, 例如： The problem is how we can get the things we need.问题是我们怎样能弄到我们需要的东西.(how 在表语从句中充当方式状语)// The scissors are not what I need. 这把剪刀不是我所需要的.(what 在表语从句中充当宾语)// What I told him was that I would find him a good play. 我告诉他的是我会给他找个好剧本.(what在主语从句中作直接宾语, that作为表语从句的引导词在该表语从句中不充当句子成分, 不能省略)// That is what I want to tell you.那就是我想要对你讲的.(what在表语从句中充当直接宾语)// That is why she failed to pass the exam. 那就是她考试不及格的原因.(why 在表语从句中充当原因状语)
注意： “That is why...”是常用句型, 意为“这就是……的原因/因此……”, 其中why引导的名词性从句在句中作表语, 该句型通常用于针对前面已经说明过的原因进行总结, 又如： That is why you see this old woman before you know, Jeanne. 珍妮, 这就是现在这个老太婆出现在你面前的原因.(前文提到Jeanne对老妇人显得苍老憔悴深感诧异, 说话人对她讲述了其中的原因之后,用这一句来进行概括).// That is why I came. 这就是我来的原因.
下面是两个与“That is why...”形式相似的结构, 它们与“That is why...”结构之间的关系要能够辨析清楚：
(1)“That is why...”与“That is the reason why...”同义, 只不过从语法结构上讲, “That is the reason why...”中why引导的是—个定语从句, 将其中的the reason去掉则与“That is why...”结构一样, 例如：
That is (the reason) why I cannot agree. 这就是我不能同意的理由.
(2)“That is because...”句型中从属连词because引导的名词性从句在此作表语, 这也是个常用句型, 意为“这就是为什么……/因为……”.“That is because...”与“That is why...”之间的不同在于“That is because...”指原因或理由, “That is why...”则指由于各种原因所造成的后果, 例如：
He did not see the film last night. That is because he had to help his little sister with her homework.昨天晚上他没有去看电影, 那是因为他得帮助他的妹妹做作业.(第一句话说明结果, 第二句话说明原因)
He had seen the film before. That is why he did not see it last night.他以前曾看过那部电影, 因此他昨天晚上没有去看.(第一句话说明原因, 第二句话说明结果)

同位语从句
一、在复合句中用作同位语的从句叫同位语从句.它一般跟在某些名词后面,用以说明该名词表示的具体内容.如：
I heard the news that our team had won．我听到了我们队获胜的消息.
I had no idea that you were here．我不知道你在这里.
二、可以跟同位语从句的名词通常有news,idea,fact,promise,question,doubt,thought,hope,message,suggestion,words（消息）,possibility等.如：
I’ve come from Mr wang with a message that he won’t be able to see you this afternoon． 我从王先生那里来,他让我告诉你他今天下午不能来看你了.
三、英语中引导同位语从句的词通有连词 that,whether,连接副词 how,when,where等.（注：if,which 不能引导同位语从句.）如：
l have no idea when he will be back．我不知道他什么时候回来.
He must answer the question whether he agrees to it or not.
他必须回答他是否同意这样一个问题.
四、有时同位语从句可以不紧跟在说明的名词后面,而被别的词隔开. 如：
Several years later,word came that Napoleon himself was coming to inspect them．
几年以后,有消息传来说拿破仑要亲自视 察他们.
The thought came to him that maybe the enemy had fled the city．
他突然想起可能敌人已经逃出城了.
五、同位语从句与定语从句的区别.
1、同位语从句与前面的名词是同位关系,即说明它前面名词的内容；而定语从句与前面的名词是修饰与被修饰关系,即限定它前面的名词范围,或补充一些情况.如：
The news that l have passed the exam is true．我通过了考试这一消息是真的.
（同位语从句,即从句所表达的意思就是前面名词的内容.）
The news that he told me just now is true．他刚才告诉我的消息是真的.
（定语从句,从句对前面名词起修饰限制作用,即“他告诉我的”那个消息,而不是别的消息.）
2、关系词在句中是否做成分 .如：
The idea that computers can recognize human voices surprises many people.
计算机能够识别人的声音的想法使许多人感到惊奇.（that在从句中不充当任何成份.）
The idea that he gave surprises many people．他提出的观点令许多人感到吃惊.
（that在从句中作gave的宾语.）
3、从句是否有疑问的意义.如：
eg.Do you remember the day when i told you that i loved you?(when引导的从句不表示疑问,所以这是一个定语从句.）
eg.I have asked the question why it was true just now.(why引导的从句表示疑问,所以这是一个同位语从句.）
一个名词(或其它形式)对另一个名词或代词进行修饰,限定或说明,这个名词(或其它形
式)就是同位语.同位语与被它限定的词的格要一致,并常常紧挨在一起.
宾语从句
学习宾语从句要抓住三要素：连接词、语序和时态.

1.连接词
连接词一般都是that(指事务或人),which（指事）,who（指人）
1．从句为陈述句,常选择连接词that或将that省略,直接与主句相连.
2．从句为一般疑问句,常选择连接词if或whether.在 whether … or not 结构中不能用 if 替换.
3．从句为特殊疑问句,常选择what,when,where,which,who,how等的疑问代、副词作连接词.
注意：当who为主语时,句式为：who+谓语+其他

2.判断时态情况：
1.主句是一般现在时,从句为各种时态情况.
2.主句是一般过去时,从句为各种相应过去时态注意：从句描绘客观事实,用一般现在时.
eg:
1. The teacher told the children that the sun＿＿＿＿ round.
A. was B. is C. were D. are
2. I believe that our team＿＿＿＿ the basketball match.
A. win B. won C. will win D. wins
3. I don’t know＿＿＿＿ to visit the old man.
A. whether B. if C. that D. who
4.The soldiers soon reached( )was once an old temple( )the villagers used as a school.
A.which;where B.what;which C.where;which D.what;where
答：选B,动词reach后接宾语从句,从句缺少宾语,where不可,which引导宾语从句时表疑问含义“哪一个…”而此句中并非疑问含义,不知道哪一座庙宇,而是用what从句表陈述含义,意“过去的一座旧庙宇”；temple后为对其修饰的定语从句,用关系代词which代替,并在从句中作动词used的宾语,use sth. as…“把…用作…
宾语从句用作宾语.如：
Do you know where he lives?
定语从句相当于一个形容词,用于修饰前面的名词.如：
The student who answered the question was John. 回答问题的学生是John.
This is the man whom he is looking for.
Do you know the girl who is in red?
语法~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
宾语从句的用法
1.that引导宾语从句无意义,不充当句子成分常省略.但下列情况除外：
（1）介词宾语从句的that不省略
（2） and连接的几个从句,第二个从句以后的从句的that不省略.
He told me that he had two sons and that they both had gone to college.
（3）在动词+it+宾语补足语+宾语从句结构中,that不省略.
I heard it said that he had gone abroad
We found it impossible that he could finish it in such a short time
2.Whether ,if 引导宾语从句：两词可互换,但是下列情形除外：
（1）whether从句中有or not
（2）whether从句做介词宾语
Everything depends on whether you agree with us
3.许多带复合宾语的句子,宾语从句经常移到句子后部,而用it做形式宾语.结构常是：
主语+动词+it+形容词/名词等宾语补足语+宾语从句
We think it wrong that he told a lie to everyone
4.宾语从句的语序要用陈述句语序
False: He is wondering when can he finish this difficult job.
Right: He is wondering when he can finish this difficult job.
B 有时候可以用it 作形式宾语