This knowledge is often (14) great help to the police.14 which word is best A OF B TO C WITH
问题描述：
This knowledge is often (14) great help to the police.14 which word is best A OF B TO C WITH
答
嗯 选of
be of help= be helpful
同样 类似的还有be of great importance = be very important
答
of+adj+抽象名词=抽象名词对应的形容词
所以,of great help=helpful,选 OF
答
选A,of+名词 意思就是这个名词对应的形容词