Complex sentence: He graduated in Classics ("lettere classiche") from the University of Padua, and became politically active during the years of the Nazi occupation of Italy, and was subsequently a leading member of the Italian Socialist Youth.
Split into simpler sentences: He graduated in Classics ("lettere classiche") from the University of Padua. He became politically active during the years of the Nazi occupation of Italy, and was subsequently a leading member of the Italian Socialist Youth.