call-circuit button

例句：

1. 1.The call-circuit button is located on the side of the phone.
   呼叫电路按钮位于电话侧面。
2. 2. The circuit button is responsible for turning on and off the lights in the room.
   电路按钮负责开启和关闭房间内的灯光。
3. 3.The call-circuit button allows you to make a call without having to press the phone key.
   呼叫电路按钮允许你无需按下电话键即可拨打电话。