表语从句-引导词(2页).doc

-表语从句-引导词-第 2 页表语从句连接词：that / whether /as if /as though连接代词：who / whom / whose / which / what 连接副词：when / where / why / how / because 1) that 在从句中仅起连接作用，无实际意义，在句中不做任何成分，不能省略。2) whether在表语从句中表 是否 但不充当句子的成分。if 不能 引导表语从句.如:1. What the doctor really doubts is whether my mother will recover from the serious disease soon.2. The question is whether it is worth doing. 3) What在表语从句中充当主语宾语表语，表示什么，什么样子，的人或事.1. The question is what caused the accident. 2. That mountain is no longer what it used to be .3. What he told you was what had been discussed at the meeting.4) who 在表语从句中充当主语，宾语，表语，表示谁。.1. The problem is who could do the work2. My trouble is who (whom) I can turn to.5) which 在引导表语从句时,常充当定语，表语表示哪一个，哪一些。如： I read about it in some book or another, but what I dont know is which (book) it is. 6) 由as if, as though引导表语从句，表示好像。句子中的系动词常用be, look, appear, seem, sound等。1. It looks as if it was doing to rain.2. The young man with long hair looks as if he were a girl.7) 当主句的主语为reason,或者是由why引导的从句时,与它们相关的表语从句用that来引导,而不能由because引导；because 引导表语从句时只能用于It/That/This is /was because句型中. 1. The reason why I was late was that I missed the train.2. I was late. It/That/This was because I missed the train.注意：当表语从句中主语、宾语、表语具备，但是还是要表示疑问含义，可以判断句子中缺少状语，常常用相应的特殊疑问词引导，有why, when, where, how等This is how he did it.That is why the brothers wanted to make a bet.Thats why weve given you the letter.表语从句引导词注意事项1. that引导表语从句时不能省.2. if不能引导表语从句.3. 除that外的所有引导词都有自己的意义。4. 除that, whether外的所有引导词都须在从句中充当相应的成分