Final answer:
The given sentence is a run-on sentence and can be corrected by dividing it into two separate sentences.
Step-by-step explanation:
The given sentence, "The hero who is a symbol of hope and the one who is known as a monster are best friends," is a run-on sentence. To correct it, you can divide it into two separate sentences to ensure clarity and proper grammar. For example, "The hero, who is a symbol of hope, is best friends with the one who is known as a monster."
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