a closed-circuit television的用法和样例：
- There is a closed circuit television and hi-fi system in the room.
- A closed circuit television camera has been installed by the Food and Environmental Hygiene Department in the side lane of Sai Yee Street and two offenders were caught red-handed.
- Guest: Next Moday. By the way, is there a closed circuit TV?
- The plant is operated entirely by remote control and monitored by closed circuit television or periscope.
- To enhance security, a new Closed Circuit Television System was installed in Mongkok Sub-office.