It is time the authorities concerned took proper steps to solve the traffic problems
问题描述：
It is time the authorities concerned took proper steps to solve the traffic problems
这里的concerned不是形容词么,形容词不是应该放在名词authorities前面表示有关的么?为什么是放在后面.究竟有没有什么规定?
答
这里的concerned不是形容词,而是过去分词,是which were concerned 的省略形式,修饰the authorities