secret switch

例句：

1. 1. The secret switch was used to hide the hidden compartment.
   秘密开关被用来隐藏隐藏的隔间。
2. 2. The secret switch was a key to unlocking the safe.
   秘密开关是打开保险箱的关键。
3. 3.The secret switch controlled the elevator's speed.
   秘密开关控制电梯的速度。