Complex sentence: Prime Minister, Margaret Thatcher, 1979--1990, was Conservative MP for Finchley from 1959 to 1992, although she never lived in the area, preferring Dulwich and Chelsea before and after her time in Downing Street.
Split into simpler sentences: Prime Minister, Margaret Thatcher, 1979--1990, was Conservative MP for the Finchley constituency from 1959 to 1992. She never lived in the area, preferring Chelsea before her time in Downing Street.