English definition of “do”
weak /də/ auxiliary verb (doing, did, done)
A1 used with another verb to form questions and negative phrases: Do you need any help? I don’t know.
A2 used at the end of a sentence to make it into a question: Sarah lives near here, doesn’t she?
B1 used to avoid repeating a verb that has just been used: ‘I hate that song.’ ‘So do I.’
› used to make the main verb stronger: He does like you – he’s just shy.