开关

例句：

1. 1. The light switch is on the wall above the door.
   灯的开关在门上方的墙上。
2. 2. Please switch off the lights when you leave the room.
   当你离开房间时，请关闭灯光。
3. 3.The computer has a built-in switch for turning it on and off.
   电脑有一个内置的开关，可以打开和关闭它。