1、表语从句在复合句中，位于系动词之后作表语的从句称为表语从句。一、that，whether引导的表语从句观察例句1The trouble is that I have lost his address.2What he wants to know is whether we can finish our work by tomorrow morning.归纳用法1连接词that在从句中只起到连接作用，不作任何成分。2连接词whether起连接作用，意为“是否；究竟；到底”，在句中不作任何成分。二、as if/though，because，why引导的表语从句观察例句1It sounds as i
2、f/though someone is knocking at the door.2Thats because he didnt understand me.3Thats why he got angry with me.归纳用法1as if 引导表语从句时，可以和as though互换。2as if/though引导的表语从句常置于系动词look，seem，sound，be，become等后面。3Thats because.强调原因；Thats why.强调结果。名师点津reason作主语时，后面的表语从句表示原因时要用that引导，不宜用because。即学即练1单句语法填空The rea
3、son why I was sad was that he didnt understand me.What cost him his life was that he was too careless.All shes worried about is whether he is all right.From space，the earth looks blue.This is because about seventyone percent of its surface is covered by water.三、连接代词和连接副词引导的表语从句观察例句1The problem is wh
4、o we can get to replace her.2Be sure to be with a strong awareness that you are what you eat!3The question is how he did it.4Their difficulty is where they can raise enough money.归纳用法1连接代词who，whom，whose，what，which，whoever，whatever，whichever在表语从句中充当主语、宾语或定语。2连接副词where，when，how，why在表语从句中充当状语。即学即练2单句语法
5、填空Grandma pointed to the hospital and said，“Thats where I was born.”They never get angry and are always kind to the students.Thats why the children can always get on well with their robot teachers.What puzzles me is how you could tell he was a thief when you first saw him.What worries us most is who
6、 let out of the secret.单句语法填空1The trouble is that I cant find my way.2Without his support，we wouldnt be where we are now.3This is what my father has taught meto always face difficulties and hope for the best.4By boat is the only way to get here，which is how we arrived.5He got caught in the heavy tra
7、ffic.That was why he was late.6Energy is what makes things work.7We didnt set out; it was because we wanted to wait until our mother came back.8The most pleasant thing of the rainy season is that one can be entirely free from dust.完成句子1It looks as if/though he were drunk.看起来他好像喝醉了。2The question is who is to blame for this accident问题是谁对这起事故负有责任。3My belief is that I will succeed by working hard.我相信通过努力我会成功的。4Jane is no longer what she was ten years ago.简再也不是十年前的那个样子了。5The fact is that our team has won the game事实就是我们队已经赢得了比赛。