that引导的宾语从句
that引导的宾语从句指的是that为宾语从句的引导词。宾语从句：置于动词、介词等词性后面，在句子中起宾语作用的从句叫做宾语从句。宾语从句分为三类：动词的宾语从句，介词的宾语从句和形容词的宾语从句。
that引导的宾语从句(在非正式场合that可以省略)
可跟that从句做宾语的动词
say, think, insist, wish, hope, demand, imagine, wonder, know, suppose, see, believe, agree, admit, deny, expect, explain, order, command, feel, dream, suggest, hear, mean, notice, prefer, request, require, propose, declare, report等。
例句：The boy believes that he will travel through space to other planets.
注意事项：当主句谓语动词是think, believe, suppose, expect等词，而宾语从句的意思是否定时，常把否定转移至主句表示。
例句：I don’t think it is right for him to treat you like that.
在以下情况中that不能省略
1、当句中的动词后接多于两个由that引导的宾语从句时，第一个that可省，但后面的that不可省。
例句：He said (that) you were too young to understand the matter and that he was asked not to tell you.
2、当主句的谓语动词与that宾语从句之间有插入语时，that一般不可省。
例句：Just then I noticed, for the first time, that our master was wearing his fine green coat and his black silk cap.
3、当that从句是双宾语中的直接宾语时，that不可省。
例句：I can’t tell him that his mother died.
注意事项：许多带复合宾语的句子，that引导的宾语从句经常移到句子后部，而用it作形式宾语。
例句：I find it necessary that we should do the homework on time.
宾语从句的特点
1.宾语从句可以作及物动词、介词及形容词的宾语。
2.宾语从句的语序一律用陈述句语序。
3.连接词that引导宾语从句在句中无词义，不充当句子成分，口语中一般可以省略。
4.whether和if都可引导宾语从句，但whether后可紧跟or not；whether从句可作介词的宾语。当if/whether引导宾语从句时，在从句中不做任何成分，但有具体的含义，意为“是否”。if/whether不能省略。
5.如果从句太长，可以用形式宾语it。
补充：从句在句子中起宾语作用的从句叫做宾语从句。
