给悉尼大学语言班写一封请求结束语言班课程并请求退费的请求信，要求不要因为是自身的原因导致的无法参与后续课程，语气一定要委婉、客气、恭敬，但是也一定要有极强的说服力。并且100字英文。

Dear Sir/Madam, I am writing to request the termination of my language course at the University of Sydney and a refund of the remaining fees. Due to unforeseen circumstances, I am unable to continue with the course and would appreciate your understanding in this matter. I understand that there may be policies in place regarding refunds, but I kindly ask for an exception to be made in my case. I assure you that this decision is not due to any fault on the part of the university or its staff, but rather a personal matter that requires my immediate attention. I have greatly appreciated the education and support provided by the language program and hope to return in the future when circumstances permit. Thank you for your time and consideration. Sincerely, [Your Name]