Re: How to address a young or elderly lady and man
In British English, police officers, customs officials, shop assistants and restaurant staff may use 'sir' and 'madam' when addressing adults. They generally use no form of address when addressing young people.
Most of us do not use any form of address when speaking to people whose name we don't know. We simply have no BrE equivalent yo the French 'monsieur/madame', the Spanish 'seņor/seņora', etc
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