be on the alert meaning in English

保持警惕
处于戒备状态

Her fears had always been on the alert for an upheaval .
她日夜提心吊胆，严防突变。
Troops are on the alert against any possible aggression
军队戒备着可能的来犯。
The public should be on the alert during thunderstorms
市民对雷暴必须提高警觉。
Troops are on the alert against any possible aggression
军队戒备着可能的来犯
Police warned the public to be on the alert for suspected terrorists
警方警告群众警惕涉嫌的恐怖分子

More: Next