㈠ 如何区分名词性从句
名词性从句是在句子中起名词作用的主谓结构，它可以在主从复合句中作主语、宾语、
表语、介词的宾语以及同位语。
1.
主语从句
主语从句可以由连词that,
wh-疑问词或名词性关系词引导。
⑴由连词that引导：从句可以位于句首，但常常用形式主语it替代，从句本身则放在
主句后面，如：
That
he
will
come
to
the
party
is
certain.
It
happened
that
the
harvest
was
bad
that
year.
Is
it
true
that
she
has
never
been
there?
通常在口语或非正式文体中，that常可省略，但必须是在用先行词it的情况下，如：
It’s
a
pity
(that)
you
are
leaving.
⑵由wh-疑问词引导：从句既可以前置，又可以借助于先行词it后置。如：
Who
cleaned
the
meeting
room
is
unknown.
It’s
still
a
question
when
we
shall
have
our
sports
meet.
It
is
uncertain
whether
he
will
come.
注意：在疑问句中，wh-疑问词所引导的从句不能位于句首，如：
Is
it
known
where
she
went?
⑶主语从句也可由名词性关系词引导，这类从句只能位于句首，如：
Where
she
went
was
Los
Angeles.
What
will
be,
will
be.
Whomever
you
invite
will
be
welcome.
2.
宾语从句
⑴宾语从句可用that引导，这时that仅起连接作用，不充当从句中的成分。如果连接词
要在从句中起语法作用，就要使用连接词what等来引导从句。
I
believe
that
he
is
honest.
We
fully
understood
what
he
meant.
⑵有些形容词的后面也可跟宾语从句。这类形容词有：certain,
afraid,
aware,
sorry,
sure,
worried等。如：
I’m
afraid
that
you
are
wrong
on
this
point.
I
am
aware
that
you
have
been
exceptionally
kind
to
me.
⑶宾语从句也可以用how,
when,
who,
which,
where,
why等词引出，此时即使主句是一
个疑问句，宾语从句也必须保持陈述句的语序。如：
Go
and
ask
why
he
was
late
yesterday.
Can
you
tell
me
where
the
hospital
is?
⑷跟在介词后面的宾语从句一般不能由that来引出，只限于except,
in,
but,
besides,
save
等五个介词的宾语从句，其它介词后面不能跟由that引出的宾语从句，而只能跟由what,
how,
whether等引出的宾语从句。
You
are
wrong
in
that
you
took
effect
for
cause.
I
would
go
with
you,
except
that
I
have
to
work
that
day.
They
were
arguing
about
what
was
to
be
done.
I’m
thinking
of
whom
I
should
ask
for
help.
3.
表语从句
表语从句通常由that引出，当然how,
why,
where,
when等也可以引出表语从句。常见的
表语从句有下面两种句型：
⑴"The
reason…that"：表示“原因是……”。如：
The
reason
for
leaving
was
that
it
was
too
cold.
⑵"It
(This,
That)
is
because…"：表示“这是因为……”，“这是由于……缘故”。如：
This
is
because
iron
contains
more
carbon
than
steel.
4.
同位语从句
同位语从句表示与之同位的名词中心词的实际内容。
⑴同位语从句起进一步解释说明先行词的作用，通常由that引导。同位语从句的先行词
通常是一些抽象名词，如：appeal,
idea,
truth,
fact,
theory,
belief,
plan,
hope,
proposal,
rumor,
suggestion等。
There
is
truth
in
the
old
saying
that
necessity
is
the
mother
of
invention.
⑵由wh-疑问词引导，如：
I
have
no
idea
when
he
will
come.
It
is
difficult
to
answer
your
question
why
I
did
it.
⑶由名词性关系词引导，如：
Fame
and
fortune—what
others
sought
after
with
zest—was
all
rubbish
to
him.
⑷注意同位语和that引导的定语从句的区别：that在同位语从句中只起引导从句的作用，
本身并无意义，也不在句子中担当任何成分；而定语从句的that既引导从句又充当句子成分。
The
news
that
he
intended
to
come
gave
us
much
pleasure.（同位语从句，that不作句子成
分。）
He
is
the
best
speaker
that
addressed
the
meeting.（定语从句，that在从句中作宾语，指代
的先行词是主句中的主语。）
㈡ 怎样区分名词性从句和定语从句
说白了，名词性从句就可以看成一个名词，就是说没了这个从句，句子就缺了一个成分，可能是主语，可能是宾语，总之缺了一部分，句子不完整。
比如，what
i
need
is
you.
如果少了what
i
need这个句子就缺主语，句子结构就有问题。
而定语从句是说，本来句子是完整的，你加上了一部分，或者是补充内容，或者是限定内容，但它的存在不影响句子的完整性。
比如，the
only
one
who
i
need
is
you.
如果少了who
i
need,省下the
only
one
is
you是个完整的句子，句子结构没问题。
㈢ 怎么区分名词性从句和定语从句
名词性从句指宾语从句、主语从句、表语从句和同位语从句，顾名思义，从它们充当的成分就可以辨别。
定语从句是跟在名词后面修饰或限定该名词的语法成分。
因为 that 引导的同位语从句和定语从句都跟在名词后面，初学者容易混淆。区别的明显特征如下：
1、同位语从句中的 that 只代表一个语法符号，不充当句子成分；定语从句中的 that 在从句中充当主语、宾语或表语，属于必不可少的语法成分。
2、同位语从句是对前面抽象名词的具体解释，而定语从句对包括具体名词和抽象名词的限定或描绘。
㈣ 英语中名词性从句的几中区别方法
主语从句、表语从句、宾语从句、同位语从句在复合句中起名词的作用，这四种从句合称名词性从句。它们在主句中充当主语、表语、宾语或同位语，都不能用逗号与主句分开。(注：句中划线部分为从句)
■主语从句
1、定义：先找到句子的谓语，主句的谓语前面的从句，叫做主语从句。
Why he left wasn't important.(wasn't是主句的谓语动词，why he left做主语从句)
That she became an artist may have been e to her father's influence.(may have been e是主句的谓语动词，that she became an artist做主语从句)
2、借助形式主语it，主语从句放在后面
①由that引导的主语从句可以放在主语的位置，这时that不可以省略。例如：That prices will go up is certain.
that主语从句放在句首的情况不是很常见，绝大部分主语从句都借助形式主语it，主语从句放在后面。
It is strange that he knows nothing about it.
It is a pity that he can't swim.
It happened that he wasn't in that day.
It is said that there has been an earthquake in India.
在口语中，用it做形式主语时，主语从句的that可以省略。
②wh-疑问词引导的主语从句，可以放在句首(第一组)，也可以借助形式主语it(第二组)。
第一组：When he'll be back depends much on the weather.
How it was done was a mystery.
Whether we'll succeed remains to be seen.
第二组：It is uncertain whether the game will be held.
It's a puzzle how life began.
It doesn't matter much where we live.
Is it known where he went？
■宾语从句
1、定义：及物动词(第一组)和介词(第二组)的后面可以接从句做宾语，叫做宾语从句。
第一组I guess(that) we'll leave soon.
He asked when we would be in London.
She informed me (that) she was to send for it the next day.(that可以省略)
I'll tell you what I read in today's paper.
第二组
I'll find out whether she's interested in going.
Can you give us a description of what has happened.
She was shocked by what she had seen.
2、借助形式宾语it，that引导的宾语从句放在后面。I've heard it said that you have won a scholarship.
分析：it在句中做形式宾语，said做宾语补足语，that you have won a scholarship是真正的宾语。She has seen to it that all the children are well taken care of.
分析：it在句中做形式宾语，that all the children are well taken care of是真正的宾语。
■表语从句
1、定义：系动词的后面可以接句子做表语，叫做表语从句。
The fact is that she never liked him.
That is not what I meant.
The question is who is responsible for what has happened.
She is no longer what she used to be.
2、注意：
①The reason Hollywood was a good place for making movies was that the sun shines there every day.
分析：the reason做主语时，表语从句用that引导。
②引导表语从句的that一般不省略。
■同位语从句
1、定义：有些名词的后面可以跟that引导的从句，说明这个名词的内容，这样的从句叫做同位语从句。所以，只有可以有内容的名词才可以接同位语从句，例如：fact，message，idea，possibility，conclusion，thought，news，order，report，rumor等等。
that在从句中不做成分，但是不能省略。
He had the feeling that he would not see her again.I've come to the conclusion that it won't be wise to do so.
2、有时为了保持句子的平衡，同位语从句有时和前面的名词分开。
The rumor spread that a new school would be built here.
that引导的同位语从句修饰the rumor，但是主句The rumor spread太短，如果把后面的同位语从句放在the rumor后面，主语太长，给人头重脚轻的感觉。
3、在少数情况下，名词性从句的其他关联词也可以引导同位语从句。但if不可以引导同位语从句。
You have no idea how worried I was.
I have no idea why she left.
There is some doubt whether John will come on time.
在学习名词性从句时注意下面四点：
一、名词性从句要用陈述语序，也就是说：①名词性从句的关联词做主语的话，关联词后面接谓语动词；②名词性从句的关联词不做主语的话，关联词后面接从句的主语和谓语。
①I don't know who broke the window.(宾语从句中关联词who做主语，broke是谓语动词)
②The little boy told his mother where he found the coin.(宾语从句中关联词where不做主语，where后面接主谓部分he found)
二、感叹句做名词性从句时语序不做变化
Don't you know how excited I was then？
三、时态的呼应
某些从句(特别是宾语从句)中的动词时态，常受主句谓语时态的制约。
①如果主句谓语动词为现在时或将来时，从句中的谓语可以不受影响。例如：
Has he told you when he received the gift？
Will you tell me how you two are getting along？
②如果主语谓语动词为过去时，从句谓语一般要跟着改为相关的过去时。
I didn't know where they lived.He thought he was working for the people.asked him how long he had been waiting.
③但是，当宾语从句表示永恒真理时谓语可以不变：This proved that the earth is round.
四、当and连接两个that引导的宾语从句时，and后面的that不可以省略
She promised (that) she would come and see him sometimes and that she would never forget him.句中的第一个that可以省略，为了清楚地表示出第二个that引导的是宾语从句，第二个that不省略。
练习：判断划线部分属哪种名词性从句
1.It is certain that she will do well in her exam.
2.The foreigner expressed his hope that he was going to visit the Great Wall again.
3.She walked up to where he stood.
4.We consider it necessary that he should improve his pronunciation.
5.This is where our problem lies.
6.What they need is a good textbook
7.I don't know who broke the window.
8.She will give whoever needs help a warm welcome.
9.I have no idea whether he has finished his homework.
10.It looks as if it is going to rain.
答案：1、主语从句 2、同位语从句 3、宾语从句 4、宾语从句 5、表语从句 6、主语从句 7、宾语从句 8、宾语从句 9、同位语从句 10、表语从句
㈤ 定语从句和名词性从句如何区分
最关键的一点：名词性从句包括主语从句、宾语从句、表语从句和同位语从句，这些从句分别在整个句子中作主语、宾语、表语和同位语。而定语从句在整个句子中作定语，起修饰作用。
具体用法如下：
名词从句
名词从句有四类：宾语从句、主语从句、表语从句、同位语从句。例如：
宾语从句：I don’t know where he will go.
主语从句：Where he will go is unknown.
表语从句：The problem is how we can get so much money.
同位语从句：We all feel sorry about the news that he failed in the game.
下面几点是学习名词从句要加以注意的：
1． whether和if都可以引导宾语从句表达“是否”意，（即引导宾语从句时if和whether
可以互换）但以下几种名词从句要用whether（不用if）引导：
（1） 引导主语从句，且在句首时。例：Whether he has won the tennis is not known.(但 It is not known whether/if he has won the tennis).
（2） 引导表语从句时。例The problem is whether he can get a job.
（3） 引导同位语从句时。例：I have no idea whether he will come.
（4） 介词后的whether从句。例：I worry about whether I hurt her feelings.
2． 位于句首引导主语从句的that不可忘。
例如：That he got the first place in the competition surprised all of us.
3． 在“It is suggested/proposed/ordered/a pity/no wonder/necessary/strange/…＋
that从句”结构中，that从句谓语有时用（should）do这样的虚拟语气形式。
例如：It is suggested that we(should) improve the relations between us.
It is a pity that one(should) stay in one place all one′s life.
It is strange that she should have failed to see her own shortcomings（缺点）.
4． 在“The reason why…is that…”句式中that不要误为because.
例如：The reason why he didn′t go to school yesterday is that he was ill.
5． 名词从句中that,what用法比较：
引导名词从句的that是连词，在句中无成份，无意义，而what是连接代词，what＝the thing(s) that.
例如：It was told in yesterday′s newspaper that what the students had done was praised by the factory.
I know that he will study.
I know what he will study.
That he works hard at his lessons is known to us all.
What he works hard at is known to us all.
All I ask is that you should tell the truth./He is not what(＝the person that)he
used to be.他和以前大不相同了。
6． where在名词从句中的使用特点：
where在名词从句中有时可以变为“the place where”,有时可以变为“介词＋the place where” 形式。例如：
主从：Where(＝The place where)she has gone is still unknown.
宾从：Would you please tell me where(＝the place where) Mr Smith lives?
表从：Your dictionary remains where(＝in/at the place where)you put.
同位从：Have you any idea where(＝of the place where) she is spending her holidays?
7． 无论是哪种名词从句都是陈述语序。例如：
I know where he lives./Please tell me what her name is.
当一个特殊疑问句本身就是陈述语序（即“主＋谓＋（宾）”或“主＋系＋表”结构），将其变为间接引语（即宾语从句）时，无需改变语序。例如：
What′s the matter with him? She asked me what was the matter with him.
Who looks after your grandfather? He asked me who looked after my grandfather. ===========================================================================
定语从句
一、 定语从句与引导词
定语从句是在复合句中修饰某一名词或代词的从句。被修饰的名词或代词叫做选行词，
而引导定语从句的词叫引导词，有关系代词和关系副词两类。
懂得什么样的先行词后用什么样的引导词是学好定语从句的关键。
1． 关系代词有：that,which,who,whom,whose,在定语从句中作主语、宾语中表语，whose 作定语。代人的有：who,whom,whose,that；代物的有：that,which,whose.例如：
The man who helped you is Mr White.(who代人，在定语从句中作主语)
That is the person(whom/who/that) you want to see.(whom,who,that代人，在定语从句中作宾语，可省略)
I′m not the fool(that) you thought me to be.(that代人，在定从中作表语)
A dictionary is a useful book which(＝that) tells us the meaning of words(which或that代物，在定从中作主语)
2． 关系副词有：when(指时间)，where(指地点),why(指原因)，在定语从句中作状语。
例如：Would you suggest a time(when) we can have a talk?(when可省略)
The house where they live is not very large./This is the reason why he did not came to the meeting.
注意：不是表时间的先行词都用when引导定从，不是表地点的先行词都用where引导定从。例如：We′ll visit the factory which(＝that) makes radios.
(which或that在定从中作主语，where不可用主语，故不可用)
They still remember the happy days(which/that) they spent in Beidaihe.
(which或that在定从中作spent的宾语，when不可作宾语，故不可用)
二、限制性定语从句与非限制性定语从句
限制性定语从句和主句之间不用逗号分开，修饰主句中的某一个名词或名词词组或代
词；非限制性定语从句常用逗号和主句隔开，可以修饰主句中的某一个词，也可修饰整个句子。非限制性定语从句不能用that引导，引导非限制性定语从句的关系词不能省略。非限制性定语从句例：Li Ping′s father, who works in a factory, is an engineer./He tore up my photo, which made me very angry.(which指代主句内容，因前后两句是因果关系，此时which不可换为as。)
He is good at physics, as is known to us all.＝As is known to us all, he is good at physics.(as指代主句内容，在as is known/believed, as we all know/believe这类结构中as不可换为which)
三、 只用that引导和不用that引导的场合
1． 只用that引导的场合
1） 当先行词既包括人又包括物时：He talked about the men and the books that attracted him.
2） 指物的先行词被any, every, only, very, all, no等修饰时：These are the very points that interest me./That′s the only watch that I like most.
3） 指物的先行词被序数词或形容词最高级修饰时：The first step that we are to take is very difficult./This is the second card that he gave me.
4） 先行词是指物的不定代词all,little,few,much,及everything,anything,nothing等时：There is still much that can be done about it./Have you got everything that you need?
5） 先行词是who时：Who that have seen him does not like him?
2． 不用that的场合如下：
1）非限制性定语从句中 Last night ,I saw a very good film,which was about the Long
March .
2）介词放在关系代词之前时 This is the man from whom I learnt the news
3）句中出现了that，或先行词是that时 I have found that which I was looking for.
四、“介词＋关系代词”用法
1． 介词的确定应依据定语从句中短语的习惯性搭配，例如：Who is the girl with whom you just shook hands?(shake hands with…是习惯性搭配)
2． 介词常受先行词的制约（即介词和先行词的搭配），例如：He built a telescope through which he could study the skies.(through which 即through the telescope)
3． 当关系代词作“动词＋介词”固定短语的宾语时，此时因定短语中的介词不能拆开移到关系代词前。例如：This is the watch which you′re looking for./He is a kind of man whom you can safely depend on.
五、几个名词后的引导词
1. situation后常用where,in which引导定语从句：Can you imagine a situation where/in
which you can use the word?
2. way(方式，方法)后常用in which或that或how引导定语从句，也可省略：Do you know the way(in which/that/how) he worked out the problem?
3. “the same＋名词”，“such＋名词”，“as＋名词”后通常用as引导定语从句。
例如：I have the same dictionary as you(have)./Such a book as you bought is not worth buying.
㈥ 怎样区分各种名词性从句
简单的区别方法：在句子中做主语的是主语从句；在及物动词(词组）或者介词以及有些表示心理喜怒哀乐等的形容词后面的名词从句是宾语从句；在连系动词后面的是表语从句；在某些名词后面用来解释说明其内容的是同位语从句。
1，2，3，4，5，6，7，10，12，14，15，16，17，20，21，22，23，24，25，27，28是宾语从句。
8，9，11，13，18，19，26，30，31，33是主语从句。（注意：33题目中在fact后面要加that。）
32是同位语从句。
㈦ 英语中不同名词性从句的辨别方法
从位置来看：
主语从句：在句首，或者用it作形式主语时，在句末；
宾语从句：在及物动词或介词后；
表语从句：在系动词后；
同位语从句：在名词后，说明名词，而且从句结构完整。
㈧ 名词性从句怎么辨别
在句子中起名词作用的句子叫名词性从句 (Noun Clauses）。 名词性从句的功能相当于名词词组, 它在复合句中能担任主语、宾语、表语、同位语、介词宾语等，因此根据它在句中不同的语法功能，名词性从句又可分别称为主语从句、宾语从句、表语从句和同位语从句。
作句子主语的从句叫主语从句。
主语从句通常由从属连词that，whether，if和连接代词what，who，which，whatever，whoever以及连接副词how，when，where，why等词引导。that在句中无词义，只起连接作用；连接代词和连接副词在句中既保留自己的疑问含义、又起连接作用，在从句中充当从句的成分。
例如：What he wants to tell us is not clear. 他要跟我们说什么，还不清楚。
㈨ 如何判断名词性从句有什么方法句子成份的划分有那位高手能指教指教吗
名词性 从句 就是 名词 用 从句 的方式表达
“从句”=“名词”
就是说 名词性从句 中的 “从句” 就是 说 一个“名词”而已 因为加了（ 一点点 虽然我不认为是一点点 那些人吃饱饭么事做） 修饰的词 所以 变成了词组 然后 加了个连接词 就成 “从句” 了
用法么 都说了 “名词性 从句” 当然 是做 "名词" 用啦
成分划分 帮 判断么 举例子 就知道类
名词性 从句 4个类型 主语 宾语 表语 同位语
‘主语 从句’就是证明 ‘从句’就是在说个‘主语’
就是 那个 “名词性 从句”里的“从句”=“名词”嘛
证明 “名词”=“主语”
论证‘从句’=‘主语’
eg:【That we will win the（ match） 】is certain.
译：【我们将赢得这场（比赛）】是确定无疑了
方括号里就是 ‘从句’
小括号里的就是‘名词’
这句句子 主要 就是 说win the match 是吧 （前面那么多 都是废话）
所以‘从句’=‘名词’是吧
所以是 ‘名词性 从句’了是吧
然后 把能去掉的都去掉 （看着这么多就烦）
【前面的词都无视掉...win the match】is certain
（中文 主+谓+宾 总归知道的咯 我也不懂语法的 主谓宾 也晓得额 我相信你也一样）
XX 是 ...（举中文例子 你 是 谁 ？）
主 谓 ...（ 主语 谓语 宾语 ？）
【】里就是‘ 主语 ’了咯
所以 ‘从句’=‘名词’=‘主语’
所以 是‘主语 从句’
‘宾语 从句’
基本完全 和‘主语 从句’一样 就是 【从句】就是在说‘宾语’
证明 【从句】=宾语
eg:I don't know 【what （her father） does】.
译：我不知道【（她父亲）是做什么的】
（）里是宾语
所以 由主语从句 同理
论证得 【从句】=‘宾语’
所以 就是‘宾语 从句’
‘表语 从句’
首先 要知道什么事‘表语’额
（简单说 就是 废话）对‘主语’起到 解释 说明的作用 使 主语内容具体化
中文例子：你 是 好人
主语 谓语 表语
（你本来就是好人 很废话吧）对 ‘你’ 做出了 解释 说明 使你 具体化成 ‘好人’（虽然 我不说 你也还是是 好人）
这个是 ‘表语’
论证 还是 一样的 证明：【从句】=‘表语’
eg:The trouble is 【that I have never done the work before】.
译：麻烦 是 【我以前从未干过这个工作】
主语 谓 【表】
（让你做了 管你以前 做没做过 没做过 就现在做额 你说了 就能不做了？那你明天别来上班了）
‘同位语 从句’
好吧 不得不说 ‘同位语’其实 帮 ‘表语’ 差不多 都是 说明 作用
‘表语’ 是废话
‘同位语’是理想化
eg：（表） 问题 是 [我不知道]
主语 谓语 [表语]
The question is [I don't know]
（同位语） 你 做过 承诺 【-- 你和我永远在一起】
主语 谓语（动词） 名词（宾)【-- 同位语 】
You made a promise【 that you and me will together forever】（那时 我只是 说说而已）
看出不同点了么
[表语] 说的虽然 是废话 但是 是事实 说明的都是 ‘具体’ 的 名词
【同位语】么 就是 理想化了 说明 都是 ‘抽象’ 的名词
ps：连接词 帮 句子里的单词 都认识的话 就算不懂语法 也能作题目