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general::
Phrase(s): mind one’s p’s and q’s.
Prov. to behave properly; to display good manners. • When you children go to visit Aunt Muriel, you’ll have to mind your p’s and q’s; not like at home, where I let you do as you please. • We’d better mind our p’s and q’s for this new teacher; I hear he’s very strict.
McGrawhill's American Idioms And Phrasal Verbs