Final answer:
The author's main purpose in writing a story could be to persuade, inform, entertain, describe, or explain. Through the story of the former slave and the narrative around Keller, the author may aim to elicit understanding, set the stage for character development, and engage the reader with sensory details.
Step-by-step explanation:
The author's main purpose in writing a story can vary, including to persuade, inform, entertain, describe, or explain. For instance, the story of the former slave who goes back to the South to pay off his freedom may be intended to persuade readers about the enduring effects of slavery, or perhaps to inform them about historical realities post-Emancipation. In the case of the narrative involving Keller, the intent might be to describe and explain her experiences, setting the stage for her transformation, thereby giving readers a deeper understanding of her character's predicament.
Determining the author's purpose is crucial as it helps the audience grasp the significance of the narrative and what the author wants them to take away from it. The sensory details provided serve to engage the reader, and the introduction of characters shapes their expectations for the story's development.