一、引导词
1．从句为陈述句，常选择引导词that或将that省略，直接与主句相连。
2．从句为一般疑问句，常选择引导词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等疑问代词、疑问副词作引导词。 注意：当who为主语时，句式为：who 谓语 其他。
4．从句的引导词有很多，如：say, think, wish , hope, see, believe, agree, expect, hear , feel等。
二、判断时态情况
1．主句是一般现在时，从句为各种时态。
2．主句是一般过去时，从句为各种相应过去时态。
3. 当宾语从句表示的是一个客观真理或者事实真理时，即使主句是过去时，从句也用一般现在时态。 例句：The teacher told his class that light travels faster than sound.
注意：从句描绘客观事实，用一般现在时。
4．关系代词：that，who，whom,whose,which
1） The teacher told the children that the sun____ round. was B. is C. were D. are2） I believe that our team____ the basketball match. win B. won C. will win D. wins 答：1.B 2.C
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.
三、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不能省略。 ②． and连接的两个从句，两个从句的that不能省略。 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. ①．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. ②. 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. ③. 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. ④. 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.
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