Complex sentence: She gave him a great interest in culture, made him write plays, and cheered him up when he was depressed, though it is not known if she ever had any political influence; she also gave him an interest in champagne, which she liked herself.
Split into simpler sentences: She gave him a great interest in culture, made him write plays, and cheered him up when he was depressed, though it is not known if she ever had any political influence. She also gave him an interest in champagne, which she liked herself.