Complex sentence: It was in prison that he learned to read and write, being tutored by Gildardo Magaña, a follower of Emiliano Zapata, revolutionary leader in Morelos, who told him of Zapata's Plan de Ayala, repudiating Madero and calling for land reform in Mexico.
Split into simpler sentences: It was in prison that he learned to read and write, being tutored by Gildardo Magaña, a follower of Emiliano Zapata, revolutionary leader in Morelos. Magaña told him of Zapata's Plan de Ayala, repudiating Madero and calling for land reform in Mexico.