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English definition of “do”


auxiliary verb (FOR QUESTIONS/NEGATIVES)   /du/ (present tense does  /dʌz, dəz/, past tense did  /dɪd/, past participle done  /dʌn/)
used with another verb to form questions and negative sentences: Where do you work? Why don’t we have lunch together on Friday? "Didn’t you know Sophie was coming?" "Of course I did." Don’t talk about that. Note: The negative contractions are doesn’t, didn’t, and don’t.
(Definition of do auxiliary verb (FOR QUESTIONS/NEGATIVES) from the Cambridge Academic Content Dictionary © Cambridge University Press)
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