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English definition of “do”


auxiliary verb (FOR QUESTIONS/NEGATIVES)    // /du/ /duː/ (did, done)
A1 used with another verb to form questions and negative sentences, including negative orders, and sometimes in affirmative sentences for reasons of style: Where do you work? Why did you do that? Why don't we have lunch together on Friday? Doesn't Matthew look old these days? "Didn't you realize she was deaf?" "No I didn't."/"Of course I did." Not only did I speak to her, I even got her autograph!formal Never did I hear such a terrible noise. Don't (you) speak to me like that!UK Don't let's argue about it (= let's not argue about it).formal So quietly did she speak (= she spoke so quietly) that I could scarcely hear her. Little does he know (= he knows nothing about it), but we're flying to Geneva next weekend to celebrate his birthday. "I want two chocolate bars and an ice cream." "Do you now/indeed? (= that is surprising or unreasonable)." A2 used instead of the main verb in questions that are added to the end of a sentence to check information: You met him at our dinner party, didn't you? You don't understand the question, do you? used instead of the main verb in questions that are added to the end of a sentence as a way of expressing surprise: So Susannah and Guy finally got married, did they?Expressions of surprise affirmativeGrammar:DoSee moreGrammar:Do: formsDo is an irregular verb. Its three forms are do, did, done. The present simple third person singular is does:See moreGrammar:Do: usesWe use do as a main verb and an auxiliary verb. We can also use it as a substitute verb.See moreGrammar:Do as a main verbDo as a main verb has a number of meanings.See moreGrammar:Do as an auxiliary verbDo is one of three auxiliary verbs in English: be, do, have. We use do to make negatives (do + not), to make question forms, and to make the verb more emphatic.See moreGrammar:Do as an auxiliary verb: typical errorsSee moreGrammar:Do as a substitute verbWe often use do instead of repeating all the words in a clause. Do substitutes for the words we don’t repeat:See more
(Definition of do auxiliary verb (FOR QUESTIONS/NEGATIVES) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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