更正一下语法,同时稍微修改下措辞.
I am so sorry that I have to make the decision.I would like to inform you that I am applying for resignation,with my last day no later than the end of this month.
I appreciated the company very much for the chance of accepting me to work in the great team for the past 5 years.My experience here is the most wonderful memory to me.
While because of the personal reason I have to give up all of these.
I feel very sorry for leaving,and hope my decision would not trouble anyone.