vt.

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

   他提醒我晚上不要單獨出去。

   The police warned us not to go out at night.

   警察告誡我們夜間不要出門。

   They warned him of the danger.

   他們警告他有危險。

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

   氣象臺預報颶風即將來臨。

vi.

1. 發出警告；發出預告

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.