Complex sentence: Other disagreements have centered on the firm requirement for a happy ending; some readers admit stories without a happy ending, if the focus of the story is on the romantic love between the two main characters (e.g., "Romeo and Juliet").
Split into simpler sentences: Other disagreements have centered on the firm requirement for a happy ending. Some readers admit stories without a happy ending, if the focus of the story is on the romantic love between the two main characters (e.g., "Romeo and Juliet").