his parents asked him to buy( )books he found useful and nessary for his study 填whichever可以么
问题描述：
his parents asked him to buy( )books he found useful and nessary for his study 填whichever可以么
或者whatever
whichever为什么不行啊？？？
答
应该填whatever,因为buy是及物动词,后面接宾语.而found后面也需要一个宾语.所以只能是whatever.如果用whichever的话,found后面应该加上一个it或them,作为形式宾语.整句话的意思是：他的父母让他去买任何他发现对学习有帮助和需要的书籍.