A red lamp is often a danger signal.
红灯常常是危险的信号。
A red signal is often used as a danger signal.
红灯常常被当作危险的信号。
Rapid breathing is a danger signal and you should call your doctor.
呼吸急促是个危险的征兆，该去请你的医生了。
A train must not pass a signal that is at danger.
火车切不可越过危险信号。
A red light is usually a signal of danger.
红灯通常是危险的信号。
A red light is a signal of danger.
红灯是危险的信号。
A red light is usually a signal of danger.
红灯通常是危险信号。
A red light is usually a signal of danger.
红灯通常是危险信号。
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