vt.

1. 警告；告诫；提醒[（+of/against）][O2][O5]
   He warned me against going outside alone at night.

   他提醒我晚上不要单独出去。

   The police warned us not to go out at night.

   警察告诫我们夜间不要出门。

   They warned him of the danger.

   他们警告他有危险。

2. 预先通知[（+of）][O5]
   The weather station warned that a hurricane was coming.

   气象台预报飓风即将来临。

vi.

1. 发出警告；发出预告

v.

1. inform of a possible danger, problem, etc.
   ▸ (warn someone off) order someone to keep away or to refrain from doing (something).
2. give cautionary advice about actions or conduct to.