Complex sentence: That evening, the family watches a videotape of the party, laughing when Dawn falls into the water; later that night, Dawn smashes the tape to pieces and briefly brandishes her hammer over Missy as she sleeps.
Split into simpler sentences: That evening, the family watches a videotape of the party, laughing when Dawn falls into the water. Later that night, Dawn smashes the tape to pieces and briefly brandishes her hammer over Missy as she sleeps.