she want to know the reason______fewer and fewer students are showing interest in her lesson

问题描述:

she want to know the reason______fewer and fewer students are showing interest in her lesson
A.for B.why
选B解释具体一点可以举点例子谢谢

选B
解析:在这个长句中,the reason是一个先行词,后面的部分是定语从句,于是选择关系副词why .she want to know the reason这是个完整的句子的,why fewer and fewer students are showing interest in her lesson 是为了修饰这个“原因”那for 为什么不可以前面是the reason 表示“原因”,而for也可以表示原因,两者一般不同时出现在句子里。例如,可以说:She is a good teacher for her kind heart .在这里可以用for或者用because of 也可以。