signal cabin

例句：

1. 1.The traffic policeman waved his hand as a signal to stop.
   交通警察挥动手示意停车。
2. 2.The ship's horn was a loud signal for the shore.
   船的汽笛是向岸边发出的响亮信号。
3. 3.The pilot used a flashing light as a signal to land.
   飞行员使用闪烁的信号灯来指示降落。