I think (that) you turned off the light.
We know (that) women love shopping.
She believed (that) her child was premature.
只有宾语从句中的that才可以省去，其他名从that不省。
3.表语从句。“that+陈述句”在表语位置即成表语从句：
My idea is that the students should be more open to each other.
The reason is that he was careless and irresponsible.(考点)
4.同位语从句。“that+陈述句”在同位语位置即成同位语从句：
所谓同位语，就是用来补充说明名词的成分。
The rumor that Tom washed his socks once a month turned out to be untrue.
Our fathers brought forth upon this continent a new nation, conceived in liberty and dedicated to the proposition that all men are created equal.
A saying goes that tomorrow is another day.
四、一般疑问句可分别充当四种句子成分。1、一般疑问句语序变成陈述语序。2、用来whether或if引导。
1.主语从句：does she love dog-walking?
Whether she loves dog-walking or not is unknown.
2.宾语从句：外语教%育网www.exam8.com
I don’t know if/whether whether she loves dog-walking
3.表语从句：
My concern is whether you are a student or not.
4.同位语从句：
They are faced with the problems whether they should continue to play.
补充：if whether区别
1)if一般用于引导宾语从句，而whether可引导所有名词从句
If he comes or not makes no difference.
The question is if he will arrive.
2)if 不和or not直接连用，一般不说 if or not。但可以说 if … or not 。而whether没有此限制。
I don’t know if or not he arrives.
I don’t know whether or not he arrives.
五、特殊疑问句可分别充当四种句子成分。特殊疑问句变成陈述句语序。