surveillance
noun [ U ] uk/səˈveɪ.ləns/ us/sɚˈveɪ.ləns/
（尤指警察或军队的）监视，盯梢
the careful watching of a person or place, especially by the police or army, because of a crime that has happened or is expected
The police have kept the nightclub under surveillance because of suspected illegal drug activity. 这家夜总会因涉嫌非法毒品活动而被警方监视。
More banks are now installing surveillance cameras. 现在更多的银行开始安装监控摄像机。