We should stay alert to any suspicious activities.

我们应该对任何可疑活动保持警惕。

A signaller must always stay alert to avoid accidents.

信号员必须时刻保持警惕以避免事故。

I’m trying to stay alert to all the things I love about him, and let go of my petty annoyances.

我努力记着，我爱他身上的那些有点，把让我心烦的琐事抛到脑后。

Stay alert to opportunities : Many lucky breaks are really the result of people seizing opportunities.

盯紧机会 : 很多幸运的突破都是人们抓住了机会的结果。 所以说一个好的想法就是在任何可能的时候拓展你的关系网多和别人交往。

He and other experts say that keeping close tabs on patients' heights can be a simple and inexpensive way for doctors to stay alert to other health problems.

他和其他专家说，密切监测病人的身高是简单而廉价的方法，有助于对病人的其他健康问题保持警觉。