Complex sentence: The first president of Egypt was Muhammad Naguib, one of the leaders of the Egyptian Revolution of 1952, who took office on 18 June 1953, the day on which the constitutional monarchy of Egypt was overthrown.
Split into simpler sentences: The first president of Egypt was Muhammad Naguib, one of the leaders of the Egyptian Revolution of 1952. He took office on 18 June 1953, the day on which the constitutional monarchy of Egypt was overthrown.