vt.　警告；告诫 give notice of possible danger or unpleasant consequences; inform in advance of what may happen

　～ parent　预先通知父母
　～ police　预先通知警察
　～ teacher　预先通知老师
　～ amply　广泛地告诫
　～ earnestly　严肃地警告
　～ faithfully　忠诚地告诫
　～ graciously　有礼貌地告诫
　～ grimly　讨厌地警告
　～ solemnly　严肃地警告
　～ subtly　巧妙地告诫
　～ sufficiently　充分地告诫
　～ urgently　紧急地警告
　～ about　告诫…提防…
　～ sb about the danger of　告诉某人（有）…的危险
　～...against　告诫…提防，警告…不要
　～ sb against driving on ice　警告…不要结冰的路面上开车
　～ of　发出关于…的警告，把…预先告诉
　～ sb off the land　叫某人离开这里
　～ sb to　提醒某人…

　The doctor had to warn her, she must be prepared for the worse.　医生不得不警告她，她必须做最坏的准备。
　This was a sign for sharks. They warned us and we all went ashore.　这是有鲨鱼的迹象。他们给我们提出了警告，我们都上岸了。
　If you warn the police when you go away on holiday, they will watch your house.　你外出度假时只要通知警方，他们会照看你的房子。
　He has been warned many times.　他已被警告过多次了。
　She warned that the winter would be very cold.　她曾提醒过，那个冬季将非常寒冷。
　The company warned that another 2000 to 3000 workers may come shortly.　这家公司警告说，不久可能还要再解雇2000至3000人。
　The weather forecast warned that a storm was coming.　气象预报说将有暴风雨来临。
　I must warn you seriously that you're in a very dangerous state of mind.　我必须严正地警告你，你的思想表现得太危险了。
　I have warned him that it is not allowed.　我曾警告过他，这是不能容许的。
　Did he warn you that he might be late?　他有没有预先告诉你他可能会迟到?
　They warned him that it was dangerous work, but he did not mind.　他们提醒他说，这是危险的工作，但他并不在意。
　I must warn you beforehand that I shall tell them everything.　我必须事先向你说明，我会把一切都告诉他们。
　He was warned that the small bridge was unsafe.　他被警告那座小桥不安全。
　The Swede was warned that the great man would probably ask him some questions.　他们提醒那个瑞典人，那位大人物很可能问他一些问题。
　I warned him not to do that.　我告诫他不要那样做。
　We warned him not to go skating on such thin ice.　我们警告他不要在这样薄的冰上溜冰。
　They warned the two sides not to continue the war.　他们警告双方，不要再继续打下去了。
　They warned him to be careful.　他们告诫过他要小心。
　There were spies posted outside. She warned him to be very careful.　外面有侦探，她叫他要小心。
　He was warned not to go there.　人们提醒过他不要到那里去。
　He had been warned not to tell anyone about it.　曾经叮嘱他不要和任何人讲这件事。
　We were warned to wear long pants and take sweaters for our climb.　人们曾告诉我们上山要穿长裤，带毛衣。

 ♣ warn against　(v.+prep.)
　告诫，当心，提防　advise sb to avoid sb/sth or doing sth
　He warned me against pickpockets.　他警告我提防扒手。
　The doctor warned the patient against smoking.　医生告诫病人不要吸烟。
　They warned him against swimming in that part of the river.　他们告诫他不要在这一带河里游泳。
　She warned me against being overconfident.　她告诫过我不要过于自信。
　I was once warned against him.　曾经有人警告我要提防他。
　I've been warned against that company, so I'll take a job somewhere else.　我曾被告诫要提防那个公司，因此我将在别处找工作。
　He was warned against trying to get through here.　有人警告过他，不要想从这里通过。
　Have they been warned against doing that?　有人告诫过他们别这样做吗?
 ♣ warn of　(v.+prep.)
　发出关于…的警告　give a warning about
　They warned of an approaching snowstorm.　他们发出将有暴风雪到来的警告。
　The motoring organization is warning of thick mist and blowing snow on high ground.　机动车组织发出高地将出现浓雾和风雪的警告。
　They were warned of the approach of the enemy.　有人告诉他们，敌人来了。
　They had been warned of the danger.　曾有人告诉过他们，有危险。
　The town's people have been warned of a possible earthquake.　镇上的居民预先得到通知说可能有地震。
 ♣ warn off¹　(v.+adv.)
1. 阻止…去（某处） try to prevent sb from going somewhere or doing sth, especially by threatening them
　Anne witnessed her boss bribing the tax collector. She wanted to report him, but her husband warned her off.　安妮目睹了她的老板贿赂税务员。她想告发他，但她丈夫制止了她。
2. 不许…上前 tell sb to keep away, prohibit from advancing, trespassing, intruding, etc.
　When we tried to enter the house, some men warned us off.　我们想进入房子时有几个人叫我们走开。
　The road was closed to traffic after the accident, and the police were warning everyone off.　事故发生后，那条路禁止通行，警察不让任何人到那里去。
　We wanted to have a picnic in the woods, but a large notice warned us off.　我们想在树林里野餐，可是一张很大的布告不许我们进入树林。
　The children used to be allowed on the farm, but they've been warned off since one of them let the cows out.　那些孩子们过去常被允许进入农场，但自从其中的一个孩子把牛放跑后，便不让他们进去了。
　The rider was found guilty of giving the horse drugs, and was warned off for a year.　人们发现那位骑手让马服用兴奋剂，因而取消其比赛资格一年以示惩罚。
 ♣ warn off²　(v.+prep.)
　不许靠近　tell to keep away prohibit from advancing, trespassing, intruding, etc.
　The police have put up signs to warn people off this area.　警方已竖起了标示牌，告诫人们不要靠近这一地区。
　He realized that his doctor was warning him off drink.　他意识到医生在告诫他戒酒。

 ♣ warn, caution, forewarn
　这三个词均可指警告可能的或即将来到的危险、伤害或不愉快的事。其区别是：warn强调明白无误地警告或告诫，有时含威胁意味。caution强调告诫某人对可能发生的危险或不愉快的事情多加小心，并常提出对之如何防范的忠告，强调的是动作本身。例如：
　The judge cautioned the prisoner.　法官警告了那个囚犯。
　The veteran worker cautioned me not to inspect the machine without turning off the power.　老工人告诫我要关掉电源后才能检查机器。
　forewarn　比warn有更强的“预先”意味，尽管危险不一定在眼前，暗含危险已迫在眉睫。例如：
　We had been forewarned of the risk of the fire that would break out.　已经事先警告过我们有发生火灾的危险。
 ♣ 下面两句话意思相同：
　

　我提醒他马上离开。
　［误］ I warned him leaving at once.
　［正］ I warned him to leave at once.
　［析］ 表示“提醒某人做某事”时，可用warn sb to-v的句型，不可以用warn sb v-ing句型。

　［派生词］ warning n.发出警告；受到告诫；警告，前兆‖warningly adv.警告地；引以为戒地
　［同义词］ admonish, advise, alert, notify
　［词源］　古英语wearnian（警告）