请英语好的朋友帮助纠正一下翻译错误：“我清楚的知道我应该为我在考试上糟糕的表现负上全部的。。。”

如果是求情信，请真的举例出正当合适的理由而且，文笔要简单精炼。
I know exactly I need to take full responsibility for the awful exam result. Despite of that, I am apperling for your help. My situation was too bad as （此处要给出具体的事情，需要事实的，比如医生给的证明） my doctor gave me a medical advice to take a semester break, while I did not to waste any time. Any delay for the time of graduation would cause a serious impact on me and I would like to try to get a second chance from you.
I would be much appreciated if you could offer some suggestions.

Thank you.