The format of KFC's resignation application should include the following elements. First, provide personal information, including name, position, department and contact information, to ensure that the resignation application is associated with the correct employee. Secondly, clarify the reasons for leaving, and briefly describe personal reasons, such as career development, family reasons or other personal considerations. Third, specify the date of resignation, which is to give the employer enough time to arrange replacement or make transitional arrangements. Finally, autograph the resignation application, confirm the voluntary resignation, and acknowledge the relevant responsibilities. This resignation application format can ensure the transparency and legality of the resignation process.