1. In the sample letter, fill in your personal information. Example: IL01600ZS or PS0100000.(IL is preprinted on the form. "P.S." in a letter stands for "post script," meaning you have added a piece of information after writing your letter. There are five required parts of a letter and one optional part. The five include a heading, greeting, body, closing, and signature. This grading system applies to all degree programs, including the JD, LL.M., and MJ programs. It does not apply to the pre-admission SCALES program.