warn 
英 [wɔːn]  美 [wɔrn] 
v. 警告；告诫；提醒；预告

例句：
The least I can do is warn them that there is a danger. 

我起码可以提醒他们有危险。

Friends warned me that having children was expensive. 

朋友们提醒我说养育孩子很花钱。

`War may break out,' he warned. 

“战争可能会爆发。”他提醒道。

Well, I warned you! 

哦，我警告过你的！

Mrs. Blount warned me not to interfere. 

布朗特夫人警告我不要插手。