danger signal
英
美
- danger n.【U】危险n.【C】危险物（或人）；威胁
- signal n.信号；标志v.(发信号)通知、表示adj.显著的
用作名词 (n.)
- A red lamp is used as a danger signal.
红灯用作危险信号。
- The engine also began its whistle-calls of four parts, with which it signalled danger to important crossings.
机车也开始在过重要的道口时，发出断续四响的汽笛声，作为危险信号。
