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English definition of “know”

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know

verb uk   /nəʊ/ us    /noʊ/ (knew, known)

know verb (HAVE INFORMATION)

A1 [I or T, not continuous] to have information in your mind: "Where did he go?" "I don't know." "What does it cost?" "Ask Kate. She'll know." She knows the name of every kid in the school. I don't know anything about this. [+ question word] We don't know when he's arriving. I don't know (= understand) what all the fuss is about. [+ (that)] I just knew (that) it was going to be a disaster. She knew (= was aware) (that) something was wrong. [+ obj + to infinitive ] Even small amounts of these substances are known to cause skin problems. formal The authorities know him to be (= know that he is) a cocaine dealer.A1 [T not continuous] used to ask someone to tell you a piece of information: Do you know the time? [+ question word] Do you know where the Post Office is?A2 [I or T, not continuous] to be certain: [+ (that)] I know (that) she'll be really pleased to hear the news. [+ question word] I don't know whether I should tell her or not. The party is at Sarah's house as/so far as I know (= I think but I am not certain).
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know verb (BE FAMILIAR WITH)

B1 [T not continuous] to be familiar with or have experience and understanding of: I've known Daniel since we were at school together. She grew up in Paris so she knows it well. I've seen the film "Casablanca" so many times that I know a lot of it by heart (= I know it in my memory). Knowing Karen (= from my experience of her in the past), she'll have done a good job. formal I have known (= experienced) great happiness in my life.B1 [I or T, not continuous] ( also know about) If you know a subject, you are familiar with it and understand it: Do you know about computers? She knows her subject inside out (= very well).A2 [T not continuous] If you know a language, you can speak and understand it: Do you know any French? [T not continuous] to recognize someone or something: That's Peter alright - I'd know him anywhere! I know a bargain when I see one.know how to do sth A2 to be able to do something because you have the necessary knowledge: Do you know how to print on this computer?get to know sb/sth B1 to spend time with someone or something so that you gradually learn more about him, her, or it: The first couple of meetings are for the doctor and patient to get to know each other. I'll need a few weeks to get to know the system.know sb by name to have heard the name of a person but not seen or talked to themknow sb by sight If you know someone by sight, that person looks familiar to you, but is not a friend of yours.
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know

noun uk   /nəʊ/ us    /noʊ/ informal
be in the know to have knowledge about something that most people do not have: This resort is considered by those who are in the know to have the best downhill skiing in Europe.
(Definition of know from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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