在衡水体英语作文中，80字的篇幅要求我们简洁明了地表达观点。以下是一篇符合要求的范文：
Dear John,
I am happy to inform you that I have successfully passed the English exam. Your help was invaluable. I appreciate your patience and guidance in improving my language skills. Thank you once again for your support.
Best regards,
Li Hua
这篇作文通过简短的文字表达了对朋友帮助的感激之情，并说明了考试的结果。