1.
A red lamp is used as a danger signal.
红灯用作危险信号。
2.
sound a note of alarm/danger/warning
发出警报[危险信号/警告信号]
3.
A train must not pass a signal that means danger.
火车切不可越过危险信号。
4.
Research and Design of Adaptive Intrusion Prevention System for Co-stimulated by Danger Signals
危险信号协同作用的自适应IPS研究与设计
5.
As soon as he led the conversation round to borrowing money I saw the red light.
当他一把话题扯到借债的事，我就感到了危险信号。
6.
A red light is usually a signal of danger.
红灯通常是危险的信号。
7.
A red light is usually a signal for/of danger.
红灯通常是危险的信号.
8.
A red flag is a sign of danger.
红旗是危险的信号。
9.
Some warning signs have appeared.
已出现了某些危险的信号。
10.
She went back in after the all clear was sounded.
危险解除信号响过后，她回来了。
11.
an automatic signal (usually a sound) warning of danger.
警告危险的自动信号（通常是一种声音）。
12.
a signal (usually a siren) that danger is over.
危险结束的信号（通常是警笛声）。
13.
(military) a signal to begin a withdrawal from a dangerous position.
（军事）开始从危险位置撤回的信号。
14.
(flag used as a symbol of danger,eg on roads,railways,etc)
（表示危险的）红色信号旗（如用于公路、铁路等）.
15.
Risk Degree Analysis of Unsafe Automobile Driving Behavior at Signalized Intersection
信号交叉口不良汽车驾驶行为危险度分析
16.
She sounded a note of danger.
她发出了危险讯号。
17.
The signal of carriage of dangerous goods is not shown as required; Necessary protection measures are not taken according to the characteristics of the dangerous goods
不按规定显示装载危险货物的信号；未按照危险货物的特性采取必要安全防护措施；
18.
When your boss raises his voice, remember it is always a red flag and you'd better shut your mouth.
(当你老板提高嗓门时，该记得那是危险的信号，最好少说废话。