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English definition of “know”

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know

verb  /noʊ/ ( past tense knew  /nu/, past participle known  /noʊn/) us  

know verb (HAVE INFORMATION)

[I/T] to have information in your mind; to be aware of something: [I] “Where did he go?” “I don’t know.” [T] Do you know the answer? [T] She knows the name of every kid in school. [+ question word] Do you know how to tap dance? [+ question word] We don’t know when he’s arriving. [+ (that) clause] I knew (that) something was wrong from the start. [+ question word] I want to know how much this will cost.know of If you know of someone or something, you have experience of or information about the person or thing: Do you know of a good doctor?

know verb (HAVE UNDERSTANDING)

[I/T] to agree with or understand the reasons for an action or opinion: [+ question word] I don’t know what all the fuss is about. [+ question word] “What a stupid movie!” “I know what you mean.”know what it is (like) to To know what it is (like) to be or do something is to understand because you have personally experienced it: She knows what it’s like to go bankrupt – it happened to her 20 years ago.

know verb (BE FAMILIAR WITH)

[I/T] to be familiar with a person or place: [T] I’ve known Vince since we were in elementary school. [T] She grew up in Hawaii so she knows it well. [T] Knowing Debbie (= from my experience of her in the past), she’ll do a good job.

know verb (FEEL CERTAIN)

[T] to feel certain about something: I know I’d enjoy myself if I went. [+ (that) clause] I know (that) I took those library books back. [+ wh- word] I don’t know whether or not I should go to college. [T] to feel certain about something: I know I’d enjoy myself if I went. [+ (that) clause] I know (that) I took those library books back. [+ question word] I don’t know whether or not I should go to college.

know verb (RECOGNIZE)

[T] to recognize someone or something, or to recognize the difference between two people or things: That’s Pete – I’d know him anywhere. I know a bargain when I see one!

know

noun  /noʊ/ us  

know noun (HAVE INFORMATION)

in the know Someone who is in the know has information about something: Ask Keith – he’s always in the know about upcoming projects.
(Definition of know from the Cambridge Academic Content Dictionary © Cambridge University Press)
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