Замените существительные с предлогом "of существительными в притяжательном падеже:- the flat of my mother, the children

1) the flat of my mother - my mother\'s flat, 2) the children of my sister Mary - my sister Mary\'s children, 3) the letter of my friend - my friend\'s letter, 4) the stories of this writer - this writer\'s stories, 5) the younger daughter of my brother - my brother\'s younger daughter, 6) the house of his parents - his parents\' house, 7) the rights of the women - the women\'s rights, 8) the children of my sisters - my sisters\' children, 9) the car of my grandparents - my grandparents\' car, 10) the room of her brothers - her brothers\' room.