介绍:
2.if,whether引导的名词性从句
从属连词if，whether引导的名词从句一般由疑问句或选择疑问句转换而来的
作用：与Wh-从句相同
主语：Whether this material can be used in our factory is still a problem
材料是否可以在我们厂使用是个问题
宾语：We do not know whether this material can be used in our factory
我不知道这种材料是否可以在我们这里使用
表语：The problem is whether this material can be used in our factory
问题就是这种材料是否可以在我们厂里使用
同位语：The problem whether this material can be used in our factory has not been solved
这种材料是否能用在我们厂，这还没有解决.
补充
Whether与if 均为是否意思时，下列情况whether不能被if 取代
whether可引导主语，表语，同位语，if一般只能引导句中的名词性从句
1.whether引导主语从句在句首，
2.引导表语从句
3.Whether从句作介词宾语
4.从句后有or not
5.当主句，从句主语一致时，whether引导名词性从句可以省略主语
正： Whether it is true or not, I can’t tell.
误： If it is true or not, I can’t tell.
（ ）we need it is a different matter
A.if B.whether C.that D.what
填空： I worry about ( ) I hurt her feelings. (whether/if）
正： I don’t know whether to accept or refuse.
误： I don’t know if to accept or refuse.
难点：
形容词宾语：She is doubtful whether we shall be able to come
介词宾语：I worry about whether he can pass through the crisis of his illness
3.Wh从句
引导词：连接代词：what,whatever,who,whoever,whom,whose,which
连接副词：when,where,how,why.
关系代词引导的从句
1.tell me who will go to NewYork（who 在宾语从句作will go 的主语）
2.They are talking about whom they should give more help（whom作give的宾语）
3.Do you know whose book it is （whose 作book 的定语）
4.Can you tell which is which（你能辨别哪个是哪个吗）
作用：除了that从句以外，还可以充当介词宾语，宾语补语，间接宾语
主语：How the book will sell depends on its author
直接宾语：In one's own home one can do what one likes
间接宾语：The club will give whoever wins a prize
表语：My question is who will take over the president of the foundation
宾语补足语：she will name him whatever she wants to
同位语：i have no idea when he will return
形容词宾语：I am not sure why he refused their invitation
介词宾语：That depends on where we shall go
B.Wh-从句作主语时也常用it作形式主语
Eg：it is not decided who will do that job
It remains unknown when they are going to get married.
互动： We do not know（ ）this is a true story or not .
A.whether B.that C.Which D.What
