|作者：陈根花 文章来源：本站原创 点击数： 更新时间：2008-8-14||
1. warn sb against doing sth 告诫某人不要做某事。如：
The doctor warned the patient against smoking. 医生告诫病人不要抽烟。
The teacher warned the children against playing on the street. 老师告诫孩子们不要在街上玩。
2. warn sb against [about] sb (sth) 告诫某人提防某人(某事) 。如：
He warned us against pickpockets. 他叫我们提防扒手。
The police have warned shopkeepers about the forged banknotes. 警察已通知各店主要留意假钞。
3. warn sb of sth 警告(通知)某人会有某情况。如：
We warned him of the danger. 我们警告过他有危险。
The teacher warned us of the test. 老师通知我们要考试。
【注】warn 一般不能接双宾语。上面第一句不能说成：We warned him the danger.
4. warn sb that-clause 警告某人……。如：
I have warned him that it is not allowed. 我警告过他这是不允许的。
Police warned drivers that the roads were icy. 警方提醒司机路面已结了冰。
We warned her that it would happen. 我们警告过她会发生这种事。
I warn you that it is dangerous to swim here.