Complex sentence: The dissolution of the Ottoman Empire (9 January 1792--24 July 1923) is the period that followed the decline of the Ottoman Empire, during which the various ethnic groups began revolting, marked by the Treaty of Jassy and Treaty of Lausanne.
Split into simpler sentences: The dissolution of the Ottoman Empire (9 January 1792--24 July 1923) is the period that followed the decline of the Ottoman Empire. During which the various ethnic groups began revolting, marked by the Treaty of Jassy and Treaty of Lausanne.