Railway signal
01
铁路信号, 火车信号
a sign or light beside a railway track that tells the train driver when to stop, go, or slow down
例子
The train had to stop because the railway signal turned red.
火车不得不停下来,因为铁路信号变成了红色。
When the railway signal is green, the train can continue its journey.
当铁路信号是绿色时,火车可以继续它的旅程。



























