alert
单词辨析：
〔辨析〕
主要用于祈使句，通常后接介词 of。
〔例证〕
Beware of the snake!
当心蛇！
You should beware of making hasty decisions.
作决定应谨防仓促草率。
〔辨析〕
指提醒某人对某事物引起重视，常用于 alert sb to sth 结构。
〔例证〕
She alerted her husband to the dangers of drinking.
她提醒丈夫注意喝酒的种种危害。
We often alert the public to the need for pollution control.
我们经常提醒公众注意控制污染的必要性。
相关例句：
He had been spotted by an alert neighbour.
一个警觉的邻居发现了他。
Soldiers and police have been put on alert.
士兵和警方都已进入警戒状态。
The all clear was sounded about 10 minutes after the alert was given.
警报发出10分钟后又响起解除的信号。
All the Plymouth hospitals are on red alert
普利茅斯所有的医院都处于紧急状态之中。
This is a very alert child.
这个孩子灵极了。
We were constantly on the alert against any surprise attack.
我们时时刻刻都在提防突然袭击。