That's not a doctor's hat, it's a bachelor's uniform. I wore it when I graduated in June this year. Four years after graduation, I got two certificates, one is graduation certificate and the other is degree certificate. When you graduate, one is the graduation ceremony and the other is the degree ceremony. These college students don't exist, only undergraduates exist.

Then you will wear it, too

Supplement: Generally, college students wear it when they graduate. The students in our school take the same courses as the students in the third and fourth grades, and the graduation link is the same, that is, they graduate with the undergraduates in the same grade. After writing the thesis, they will take photos of the bachelor's uniform at the graduation ceremony. In general, every student in a school will issue a set on the day of the bachelor's degree awarding ceremony and take it back after the ceremony, but each class will rent it in advance to take pictures. It was a very touching time in college.