Complex sentence: He helped to hide or rescue several Poles, including Jews, in Nazi-occupied Poland, and is perhaps most remembered for helping Polish-Jewish pianist and composer Władysław Szpilman survive hidden in the ruins of Warsaw during the last months of 1944.
Split into simpler sentences: He helped to hide or rescue several Poles, including Jews, in Nazi-occupied Poland. He is perhaps most remembered for helping Polish-Jewish pianist and composer Władysław Szpilman survive hidden in the ruins of Warsaw during the last months of 1944.