(1)警告，预先告知(give sb a caution or tell sb before what may occur)[T+n，T+n+prep(of)，D+n+that，D+n+wh-inf]：“Be careful!” he～ed me. “小心点!”他警告我说。～sb beforehand/in advance 预先通知某人;If you～the police when you go away on holiday， they will watch your house. 如果你外出度假时预先通知警察局，他们会帮你照看房子。～sb of the risk/the danger/the possible failure/the possible delay/the thick fog/the consequence of sb's action 预先告知某人有风险/有危险/可能失败/可能延误/有大雾/其行为的后果;～sb of one's intention 预先告诉某人自己的意图;The weather forecast～ed (people) of severe snowfalls ahead/the approaching storm/the floods. 气象预报(向人们)预告即将到来的大雪/暴风雨/洪水。The black clouds～ed us that a storm was coming up. 天上的乌云警示我们暴风雨即将到来。I haven't been～ed what to expect. 没有人预先通知我要发生什么。He was～ed away. 他受到警告让他离开。The landlady～ed her tenant out of the house. 女房东警告房客搬出房子。〖同〗alert，caution，foretell，inform，notice;〖反〗encourage;

(2)告诫，提防 (tell sb to guard against sth) [T+n+prep(about/against)]：A notice on each packet～s the public about the dangers of cigarette smoking. 每个烟盒上都印有告诫公众吸烟有害的提示。The staff are～ed about pickpockets/the forged bank-notes. 职员被告诫要提防扒手/伪钞。～sb against going there at night/speeding/smoking/being overconfident 告诫某人不要在夜晚去那儿/超速驾驶/吸烟/过于自信;〖同〗guard，caution，tell;

(3)建议，劝告 (give sb advice) [C+n+to-inf]：They～ed him not to be late/to go skating on such thin ice/to climb the mountain in such bad weather. 他们劝告他不要迟到/在这么薄的冰上滑冰/在这种坏天气爬山。～sb to be on lookout/to be careful/to stay away 劝告某人务必留心/小心/离开;〖同〗advise，suggest，propose;

warn away/off (v adv prep) 1)让离开(vi & vt)： The farmer～ed us off (his field)/away. 农民让我们离开(他的地)。A sign～s trespassers off the grounds.一块警示牌上写着：未经许可不得进入场地。2)不让做某事(vi & vt)：The athlete was found guilty of taking drugs and was～ed off for a year. 该运动员被发现服用违禁药物，受到停赛一年的处罚。People are～ed off speaking aloud in the ward. 劝告人们不要在病房里大声喧哗。

→′warning n 警告，告诫