Final answer:
Novels have complex main plots and subplots, short stories are concise and may include a plot twist, and novellas offer a balance between novels and short stories.
Explanation:
Novels are narratives that often contain subplots and a complex main plot, allowing for in-depth exploration of characters, settings, and events over an extended period of time. On the other hand, short stories are narratives with a concise and focused plot, usually limited in characters and setting, and often feature a twist in the ending.
Novellas, falling between novels and short stories in length, offer a balance between the depth of a novel and the brevity of a short story, making them unique in their narrative structure and development.
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