Complete the following sentence with a (compound) word derived from the one(s) given in bracket.
The policemen on patrol became （ ） of the two men in a car.(suspicion)
【正确答案】：SUSPICIOUS
【题目解析】：
本题考查的是常用名词的形容词形式。
由became可知，空缺处应该填形容词，suspicion的形容词形式是suspicious意为“对...怀疑的”，符合句意。
句意：巡逻的警察对车上的两个人起了疑心。