在复合句中用作宾语的从句叫宾语从句。
1.语序
无论主句是陈述句还是疑问句，宾语从句都必须使用陈述语序，即“主句+连词+宾语从句(主语+谓语+……)”句式。根据连接词在从句中所担任的不同成分，可分为以下四种
1)连接词+谓语。连接词在从句中作主语。常见的连接词有 who，what，which等。如
Could you tell me who knows the answer，please你能告诉我谁知道答案吗
The small children don't know what is in their stockings.这些小孩子不知道袜子里有什么东西
2)连接词+名词+谓语。连接词在从句中作主语的定语。常见的连接词有whose，what，which，how many，how much等。如
He asked whose handwriting was the best in our class.他问我们班上谁的书法最好。
The teacher asked us how many people there were in the room.老师问我们房间里有多少人。
3)连接词+主语+谓语。连接词在从句中作宾语、状语或表语。常见的连接词有who(m)，what，which，how many，how much， when，why，how，where，if whether(在句中不充当任何成分)等。如
He hasn't decided if he'll go on a trip to Wuxi.他还没决定是否去无锡旅行。
Could you tell me what I should do with the money 你能告诉我我如何处理这笔钱吗
4)连接词+名词+主语+谓语。连接词在从句中作宾语或表语的定语。常见的连接词有what，which，how many，how much，how等。如
Do you know which class he is in 你知道他在哪个班吗
She asked me if I knew whose pen it was.她问我是否知道这是谁的钢笔。
2.连接词
1)当由陈述句充当宾语从句时，用that引导，that无词义，在口语或非正式文体中常省略。如
He said that he could finish his work before supper.他说他会在晚饭前完成工作。
2)当由一般疑问句充当宾语从句时，用if或whether引导，意为“是否”。如
I don't know if whether he still lives here after so many years.我不知道这么多年后他是否还住在这儿。
但在下列情况下只能用whether
①在具有选择意义，又有or或or not时，尤其是直接与or not连用时，往往用whether(if…or not也可以使用)。如
Let me know whether if he will come or not.(=Let me know whether or not he will come)让我知道他是否能来。
I don't know whether if he does any washing or not.(=I don't know whether or not he does any washing.)我不知道他洗不洗衣服。
I wonder whether we stay or whether wego.我不知道我们是去还是留。
②在介词之后用whether。如
I'm interested in whether he likes English.我关心的是他是否喜欢英语。
We're thinking about whether we can finish the work on time.我们正在考虑是否能按时完成这项工作。
I worry about whether I hurt her feelings.我担心是否伤了她的感情③在不定
式前用whether。如:
He hasn't decided whether to visit the old man.他尚未决定是否拜访那位老人。
I don't know whether to go.我不知去否。
He hasn't decided whether to go by bus or by train.他还未决定是乘公共汽车去还是坐火车去。
④whether置于句首时，不能换用if。如:
Whether this is true or not，I can't say.这是否真的我说不上来。
⑤引导主语从句和表语从句时宜用whether。如:
Whether she will come or not is still a question.她是否能来还是个问题。
The question is whether we can catch the bus.问题是我们能否赶上公共汽车。
⑥若用if会引起歧义时，则用whether。如:
Please let me know if you like the book.可理解为:
a.Please let me know whether you like the book.请告诉我你是否喜欢这本书。
b.If you like the book，please let me know.你如果喜欢这本书，请告诉我。
3)如果宾语从句原来是特殊疑问句，只需用原来的特殊疑问词引导。如:
Could you tell me why you were late for the meeting this morning?你能告诉我今天早上你为什么开会迟到吗?
3.时态
含宾语从句的复合句，主、从句谓语动词的时态呼应应包括以下三点内容:
1)如果主句的谓语动词是一般现在时，从句的谓语动词可根据需要，选用相应的任何时态。如:
I don't know when he will come back.我不知道他将何时回来。
He tells me that his sister came back yesterday.他告诉我他姐姐昨天回来了。
2)如果主句的谓语动词是过去时，宾语从句的谓语动词只可根据需要，选用过去时态即一般过去时、过去进行时、过去将来时或过去完成时的某一种形式。如:
①The children didn't know who he was.孩子们不知道他是谁。
②He asked his father how it happened.他问他父亲这件事是如何发生的。
3)如果宾语从句所表示的是客观事实、普遍真理、自然现象或习惯性动作等，不管主句用什么时态，从句时态都用一般现在时。如:
The teacher said that the earth goes round the sun.老师说地球绕着太阳转。
4.注意:
if和when既可以引导宾语从句，也可以引导状语从句，应注意它们在两种从句中的意思和用法的不同。if和when引导宾语从句时，分别意为“是否”和“何时”，其时态应和主句时态相呼应;它们引导状语从句时，意思分别为“如果，假如”和“当……时候”，当主句时态是一般将来时时，其时态用一般现在时。它们常常放在含有状语从句和宾语从句的题干中进行综合考查。如:
-Do you know when he will come back tomorrow ?你知道他明天什么时候回来吗?
-Sorry，I don't know.When he comes back，I'll tell you.对不起，不知道。当他回来了，我将告诉你。
-I don't know if he will come.我不知道
他是否会来。
-He will come if it doesn't rain.如果不下雨，他会来的。
简化宾语从句常用六法
同学们常会遇到把含有宾语从句的复合句转化为简单句，使其与原句意思相同(或相近)的试题。下面就介绍几种常用的简化宾语从句的方法:
方法一:当主句谓语动词是hope， decide， wish， choose， agree， promise等，且宾语从句的主语与主句主语一致时，宾语从句可简化为不定式结构。例如:
Li Ming hopes he will be back very soon. →Li Ming hopes to be back very soon.
We decided that we would help him. →We decided to help him.
方法二:当主句谓语动词是know， learn， remember， forget， tell等动词，且主句主语与从句主语一致时，宾语从句可简化为“疑问词+不定式”结构。例如:
She has forgotten how she can open the window. →She has forgotten how to open the window.
注:当主句谓语动词是tell， ask， show， teach等动词，且后带双宾语，从句主语和间接宾语一致时，宾语从句可简化为“疑问词+不定式”结构。例如:
Could you tell me how I can get to the station? →Could you tell me how to get to the station?
方法三:当主句的谓语动词是order(命令)，require(需要)等时，如果主句和从句的主语不一致，宾语从句可简化为“名词(代词)+不定式”结构。例如:
The headmaster ordered that we should start at once. → The headmaster ordered us to start at once.
方法四:某些动词后的宾语从句，可以用介词加动名词(短语)等其他形式简化。例如:
He insisted that he should go with us. →He insisted on going with us.
The poor boy doesn’t know when and where he was born. →The poor boy doesn’t know the time and the place of his birth.
方法五:某些动词后面的宾语从句可转化为“宾语+V-ing形式(作宾语补足语)”结构。例如:
Liu Ping found that there was a wallet lying on the ground. → Liu Ping found a wallet lying on the ground.
方法六:动词seem后的宾语从句，也可以用不定式(短语)来简化，但句型需要进行适当的变化。例如:
It seemed that the boys were going to win. →The boys seemed to win.
除上述方法外，还有一些特殊句式的转化。例如:
I found that it was difficult to learn English well. →I found it difficult to learn English well.
Soon we found that the ground was covered with thick snow. →Soon we found the ground covered with thick snow.
They found that the box was very heavy. →They found the box very heav
在复合句中用作宾语的从句叫宾语从句。
1.语序
无论主句是陈述句还是疑问句，宾语从句都必须使用陈述语序，即“主句+连词+宾语从句(主语+谓语+……)”句式。根据连接词在从句中所担任的不同成分，可分为以下四种
1)连接词+谓语。连接词在从句中作主语。常见的连接词有 who，what，which等。如
Could you tell me who knows the answer，please你能告诉我谁知道答案吗
The small children don't know what is in their stockings.这些小孩子不知道袜子里有什么东西
2)连接词+名词+谓语。连接词在从句中作主语的定语。常见的连接词有whose，what，which，how many，how much等。如
He asked whose handwriting was the best in our class.他问我们班上谁的书法最好。
The teacher asked us how many people there were in the room.老师问我们房间里有多少人。
3)连接词+主语+谓语。连接词在从句中作宾语、状语或表语。常见的连接词有who(m)，what，which，how many，how much， when，why，how，where，if whether(在句中不充当任何成分)等。如
He hasn't decided if he'll go on a trip to Wuxi.他还没决定是否去无锡旅行。
Could you tell me what I should do with the money 你能告诉我我如何处理这笔钱吗
4)连接词+名词+主语+谓语。连接词在从句中作宾语或表语的定语。常见的连接词有what，which，how many，how much，how等。如
Do you know which class he is in 你知道他在哪个班吗
She asked me if I knew whose pen it was.她问我是否知道这是谁的钢笔。
2.连接词
1)当由陈述句充当宾语从句时，用that引导，that无词义，在口语或非正式文体中常省略。如
He said that he could finish his work before supper.他说他会在晚饭前完成工作。
2)当由一般疑问句充当宾语从句时，用if或whether引导，意为“是否”。如
I don't know if whether he still lives here after so many years.我不知道这么多年后他是否还住在这儿。
但在下列情况下只能用whether
①在具有选择意义，又有or或or not时，尤其是直接与or not连用时，往往用whether(if…or not也可以使用)。如
Let me know whether if he will come or not.(=Let me know whether or not he will come)让我知道他是否能来。
I don't know whether if he does any washing or not.(=I don't know whether or not he does any washing.)我不知道他洗不洗衣服。
I wonder whether we stay or whether wego.我不知道我们是去还是留。
②在介词之后用whether。如
I'm interested in whether he likes English.我关心的是他是否喜欢英语。
We're thinking about whether we can finish the work on time.我们正在考虑是否能按时完成这项工作。
I worry about whether I hurt her feelings.我担心是否伤了她的感情③在不定
式前用whether。如:
He hasn't decided whether to visit the old man.他尚未决定是否拜访那位老人。
I don't know whether to go.我不知去否。
He hasn't decided whether to go by bus or by train.他还未决定是乘公共汽车去还是坐火车去。
④whether置于句首时，不能换用if。如:
Whether this is true or not，I can't say.这是否真的我说不上来。
⑤引导主语从句和表语从句时宜用whether。如:
Whether she will come or not is still a question.她是否能来还是个问题。
The question is whether we can catch the bus.问题是我们能否赶上公共汽车。
⑥若用if会引起歧义时，则用whether。如:
Please let me know if you like the book.可理解为:
a.Please let me know whether you like the book.请告诉我你是否喜欢这本书。
b.If you like the book，please let me know.你如果喜欢这本书，请告诉我。
3)如果宾语从句原来是特殊疑问句，只需用原来的特殊疑问词引导。如:
Could you tell me why you were late for the meeting this morning?你能告诉我今天早上你为什么开会迟到吗?
3.时态
含宾语从句的复合句，主、从句谓语动词的时态呼应应包括以下三点内容:
1)如果主句的谓语动词是一般现在时，从句的谓语动词可根据需要，选用相应的任何时态。如:
I don't know when he will come back.我不知道他将何时回来。
He tells me that his sister came back yesterday.他告诉我他姐姐昨天回来了。
2)如果主句的谓语动词是过去时，宾语从句的谓语动词只可根据需要，选用过去时态即一般过去时、过去进行时、过去将来时或过去完成时的某一种形式。如:
①The children didn't know who he was.孩子们不知道他是谁。
②He asked his father how it happened.他问他父亲这件事是如何发生的。
3)如果宾语从句所表示的是客观事实、普遍真理、自然现象或习惯性动作等，不管主句用什么时态，从句时态都用一般现在时。如:
The teacher said that the earth goes round the sun.老师说地球绕着太阳转。
4.注意:
if和when既可以引导宾语从句，也可以引导状语从句，应注意它们在两种从句中的意思和用法的不同。if和when引导宾语从句时，分别意为“是否”和“何时”，其时态应和主句时态相呼应;它们引导状语从句时，意思分别为“如果，假如”和“当……时候”，当主句时态是一般将来时时，其时态用一般现在时。它们常常放在含有状语从句和宾语从句的题干中进行综合考查。如:
-Do you know when he will come back tomorrow ?你知道他明天什么时候回来吗?
-Sorry，I don't know.When he comes back，I'll tell you.对不起，不知道。当他回来了，我将告诉你。
-I don't know if he will come.我不知道
他是否会来。
-He will come if it doesn't rain.如果不下雨，他会来的。
简化宾语从句常用六法
同学们常会遇到把含有宾语从句的复合句转化为简单句，使其与原句意思相同(或相近)的试题。下面就介绍几种常用的简化宾语从句的方法:
方法一:当主句谓语动词是hope， decide， wish， choose， agree， promise等，且宾语从句的主语与主句主语一致时，宾语从句可简化为不定式结构。例如:
Li Ming hopes he will be back very soon. →Li Ming hopes to be back very soon.
We decided that we would help him. →We decided to help him.
方法二:当主句谓语动词是know， learn， remember， forget， tell等动词，且主句主语与从句主语一致时，宾语从句可简化为“疑问词+不定式”结构。例如:
She has forgotten how she can open the window. →She has forgotten how to open the window.
注:当主句谓语动词是tell， ask， show， teach等动词，且后带双宾语，从句主语和间接宾语一致时，宾语从句可简化为“疑问词+不定式”结构。例如:
Could you tell me how I can get to the station? →Could you tell me how to get to the station?
方法三:当主句的谓语动词是order(命令)，require(需要)等时，如果主句和从句的主语不一致，宾语从句可简化为“名词(代词)+不定式”结构。例如:
The headmaster ordered that we should start at once. → The headmaster ordered us to start at once.
方法四:某些动词后的宾语从句，可以用介词加动名词(短语)等其他形式简化。例如:
He insisted that he should go with us. →He insisted on going with us.
The poor boy doesn’t know when and where he was born. →The poor boy doesn’t know the time and the place of his birth.
方法五:某些动词后面的宾语从句可转化为“宾语+V-ing形式(作宾语补足语)”结构。例如:
Liu Ping found that there was a wallet lying on the ground. → Liu Ping found a wallet lying on the ground.
方法六:动词seem后的宾语从句，也可以用不定式(短语)来简化，但句型需要进行适当的变化。例如:
It seemed that the boys were going to win. →The boys seemed to win.
除上述方法外，还有一些特殊句式的转化。例如:
I found that it was difficult to learn English well. →I found it difficult to learn English well.
Soon we found that the ground was covered with thick snow. →Soon we found the ground covered with thick snow.
They found that the box was very heavy. →They found the box very heav