The starting and ending time of this situation is written as the admission time and graduation time.

1. Admission time: For most universities in Chinese mainland, the admission time for freshmen is usually in the autumn semester every year, that is, around September 1. If you are enrolled in the fall of 20xx, you can fill in "September of 20xx".

2. Graduation time: In most cases, the graduation time of graduates is at the end of the spring semester, which is about the end of June to the beginning of July every year. If you expect to graduate in July 1, you can fill in "July 20xx 1". If the date on the diploma is a specific date, such as June 28th or July 5th, it should be filled in according to the actual date.