He proposed to his girlfriend over a public-address system.
他在有线广播系统上向女友求婚。
《柯林斯英汉双解大词典》
2
He said they would page him over the public-address system.
他说他们会通过公用通讯系统与他联系。
3
The cones of larger loudspeakers used in traditional public-address systems vibrate more slowly, making them better suited for sounds in the range of human hearing.