be on the alert

基本解释

We must be on the alert to discharge our responsibilities toward the friendly countries.
我们必须警惕自己放弃对友好国家的责任的做法。
Our company has informed us that there have been many cases of piracy, and warned us to be on the alert .
公司已经通知我们，最近连续发生多起海盗袭击船舶事件，因此要求我港提高警惕。
Currently, first, the BRICs should be on the alert that hostile powers in developed countries may make mischief between them under the cover of ideology and history-made problems;
当前，它们一是要特别警惕发达国家中的敌对势力利用意识形态和历史遗留的问题挑拨离间；

General Fonseka,in the letter, says Sri Lanka asked India on October 15 to place troops on alert in case they would be needed to intervene to foil a coup on the island.

Planned Parenthood has to be on the alert already given the episodes over the last month.
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You can be the one to be on the alert for their financial safety.
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When a fifth wave is extended, we should be on the alert for a sharp correction once that wave completes its run.
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