如何区分英语里的宾语从句以及其他从句

Question

如题，当出现一个从句时，怎样判断是什么类型的从句？是根据先行词还是引导从句的那个词？请高手解释下，最好能说明用什么方法判断

Answer 1

要根据这个从句所在的位置和它和主句之间的关系来判断一个从句是什么从句.
一.如宾语从句就在及物动词后或是在介词后.
eg:I doubt whether he will come this afternoon.(从位置上看这是一个宾语从句)
eg:They are talking about whether they will have a picnic this weekend.(从位置上看这也是一个宾语从句)
二.主语从句在动词之前,或是在有形式主语时的句子后面.
eg:That he was late again made his teacher angry.(that引导的是主语从句)
eg:It is certain that he will win the game.(that引导的也是主语从句)
三,表语从句要在系动词之后
eg:This is what I want.(what引导的是表语从句)
四.同位语从句在名词或代词之后,对这个词进行解释说明.
eg:The news that we will have a exam is true.(that引导的是同位语从句)
五.定语从句也在一名词或代词之后,但是是对这一词的修饰限定.
eg :The news that he told us is true.(这是一个定语从句,因为先行词在从句中作了宾语)
六.状语从句有很多种,有的在主句之前,有的在主句之后,要看情况.总之是强调谓语动词发生的时间,地点.原因.条件,方式等.
eg:When I am free this afternoon, I will go to see you.(when引导的时间状语从句)
I found the book where I lost it.(where引导的是地点状语从句)
Although he was ill, Tom went on working.(although引导的是让步状语从句)

Answer 2

知道什么是并与从句了就知道怎么区分了：
宾语从句就是一个句子作动词或介词的宾语。
A 作动词的宾语:
I heard the news.
主语 谓语动词 名词作宾语
I heard that he would come here later on.
主语 谓语动词 一个句子作宾语---宾语从句
B 作介词的宾语:
He said nothing about the plan.
主语 谓语动词 代词作动词的宾语 介词 名词作介词的宾语
He said nothing about who broke the window last night.
主语 谓语动词 代词作动词的宾语 介词 一个句子作介词的宾语
二 带有宾语从句的复合句的构成:
带有宾语从句的复合句就是用连接词把一个主句和一个宾语从句连接在一起。连接词有：that(可省略)，what, who, when, where, why, which, if, whether, how.
1 He suggested (that) we should clean the corridor every day.
宾语
2 He told me (that) he would leave Dalian airport at 8pm.
间接宾语 直接宾语
3 He told me where he was going to travel that summer.
间接宾语 直接宾语
4 He wanted to know what the manager had said at the meeting.
who hadn’t passed the exam.
when she would leave this building.
why she cried last night.
where she was going to study.
which student was his partner in the short play.
if (whether) Tom could play basketball with him that morning.
how she managed to solve the problem.
why water flows from a high position to a lower position.
在例子4中，当主句是过去时态时（一般过去时，过去进行时，过去将来时，过去完成时），从句根据不同情况必须使用过去时态的一种，（大自然的现象和真理除外）。
5 He is wanting to know what I can cook for dinner.
who broke the window yesterday.
when I can have a holiday.
why I failed the exam yesterday.
where I should have dinner with my friend tonight.
which book is the best one.
if (whether) I have passed the exam.
how my cat escaped from the room last night.
在例子5中，当主语是现在时态时（一般现在时，现在进行时，一般将来时，现在完成时），从句可根据不同情况使用各种时态。
三 注意：
A 宾语从句必须用陈述语序。
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，而把真正的宾语从句放在后面。
Bad: I thought that he could finish this job in just two hours impossible.
Good: I thought it impossible that he could finish this job in just two hours.
Bad: He left whether we should continue this project to my judgment.
Good: He left it to my judgment whether we should continue this project.
C 带有宾语从句的复合句的否定形式一般是否定主句。
Bad: I think he doesn’t like the English teacher.
Good: I don’t think he likes the English teacher.
D 主句一般过去时态，从句也要用过去时态；具体细节请看第一部分。
False: He wanted to know why he is crying in the corner.
Right: He wanted to know why he was crying in the corner.

Answer 3

先看关系代词，再看先行词，之后判断从句做什么成分。
比如that前是动词，一般是宾语从句。若是名词，一般是定语从句。
主语从句，同位语从句等有些与定语从句有些像，就要看情况了。分清他们的区别就好做题了。