common battery private branch exchange

例句：

1. 1. The common battery is essential for powering the lights in the classroom.
   公共电池对于教室里的灯光供电至关重要。
2. 2.The private branch exchange is responsible for handling customer calls and providing services.
   私人交换局负责处理客户电话并提供服务。
3. 3.The common battery and private branch exchange are both essential components of a modern communication system.
   公共电池和私人交换局都是现代通信系统不可或缺的组成部分。