<Table> <Tr> <Td> </Td> <Td> Look up mind one's ps and qs in Wiktionary, the free dictionary . </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> Look up mind one's ps and qs in Wiktionary, the free dictionary . </Td> </Tr> <P> Mind your Ps and Qs is an English expression meaning "mind your manners", "mind your language", "be on your best behaviour" or similar . </P>

Where did be on your p's and q's come from