If the promisor is a student, of course, the student himself must sign, and many documents need to be signed by the student himself. For example, give students some specific notices and ask them to do something, and so on. These all need to make corresponding commitments, and these commitments are the students' own, and naturally they should be signed by the students themselves.

Under special circumstances, the promisor's student's parents or a family member can also sign, but the signature must indicate that someone has signed it.