alert的音标是əˈlɜːt。alert作为形容词时意为警觉的、敏捷的，作为名词时意为警报、警戒状态，作为动词时意为使警觉、提醒。

短语搭配：
on the alert 警戒着
red alert 紧急警报
alert system 警报系统
alert message 警报信息
high alert 高度戒备
state of alert 警戒状态

相应英文带中文翻译的例句：
1 The guard remained alert throughout the night. 警卫整夜保持警觉。
2 The company issued an alert about the product recall. 公司发布了产品召回警报。
3 She alerted the authorities to the potential danger. 她向当局提醒了潜在危险。
4 The soldiers were put on high alert during the crisis. 危机期间士兵们处于高度戒备状态。
5 The weather alert warned residents of the approaching storm. 天气警报提醒居民风暴即将来临。
6 His alert response prevented a major accident. 他敏捷的反应防止了一起重大事故。
7 The system sends an alert when temperatures exceed safe levels. 当温度超过安全水平时系统会发出警报。
8 Drivers must stay alert on foggy days. 司机在雾天必须保持警觉。
9 The security alert caused the building to be evacuated. 安全警报导致大楼被疏散。
10 We received an alert about the network outage. 我们收到了关于网络中断的警报。