Final answer:
The student is asking for assistance in writing a letter to the principal to explain a fight and defend a friend against expulsion, aiming to provide a clear and persuasive argument for the friend's reinstatement.
Step-by-step explanation:
The subject of the student's question is to write a letter to the principal explaining the circumstances of a fight and arguing why a friend should not be expelled. Crafting such a letter requires an understanding of the context, presenting any mitigating evidence, and appealing to the principal's sense of fairness and the school's policies on discipline. The goal is to provide an account that could potentially have the expulsion decision reconsidered by highlighting redeeming qualities of the involved student or questioning the fairness of the punishment.