adj.機(jī)會(huì)主義的；投機(jī)取巧的；對(duì)免疫系統(tǒng)差的人有害的
Most of the robberies have been opportunistic crimes against elderly people who live alone. 多數(shù)的搶劫是針對(duì)獨(dú)居老人的投機(jī)取巧的犯罪。
