Complex sentence: Enlisted by Gonzalo Fernández de Córdoba (1499), he took part in the capture and siege of Cephalonia (1500); his skilful employment of mines allowed for the breaching of the walls of the Turkish fortress.
Split into simpler sentences: Enlisted by Gonzalo Fernández de Córdoba in 1499, he took part in the capture and siege of Cephalonia in 1500. His skilful employment of mines allowed for the breaching of the walls of the Turkish fortress.