Because now the volunteers are basically parallel volunteer. When students fill in their volunteers, there is an admission order between the universities they report. If you are admitted to the university before the students, the universities behind you will not be admitted. If the last university is not admitted, leave the students to the next university to see if they are admitted. So there can only be one admission notice.

If students can have more than one admission notice, it is very risky for the school. It is impossible for a school to correctly estimate the number of students to report each year by mailing the admission notice, which is very unfavorable for the school to arrange teaching.