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Recently the Duchess of Cambridge gave birth to a healthy baby boy. The announcement from Buckingham Palace said "The Duchess of Cambridge has been delivered of a son."
This struck me as a very odd grammatical structure that I don't quite understand. Of course I understand what is meant: "She gave birth to a male child" and I presume it is put this way for the purposes of delicacy. But I was wondering if someone could explain how this grammatical structure works.