Complex sentence: Pinochet organized a plebiscite on 11 September 1980 to ratify a new constitution, replacing the 1925 Constitution drafted during Arturo Alessandri's presidency.
Split into simpler sentences: Pinochet organized a plebiscite on 11 September 1980. The Chilean people were asked to ratify a new constitution, replacing the 1925 Constitution drafted during Arturo Alessandri's presidency.