Schema.org defines generic types.

For example it defines Person here https://schema.org/Person

It defines properties like for example alumniOf meaning "what place he/she studied in". Textually "An organization that the person is an alumni of."

Okey, but...

What happens if this person studied in multiple places?

If I change the type and set an array instead of an EducationalOrganization or Organization I am breaking the schema.

Same happens with the album property of the MusicGroup https://schema.org/MusicGroup although here we find a tip: Time ago there was an albums in plural now superseeded by the album in singular.

This suggests that maybe schema.org already defines a way to use "one" or "more" items in a property in some standardized way... For example the Organization https://schema.org/Organization defines the email but what if it has 3 "official" email addresses.

Question

Does schema.org define some interop standardized way to model properties with one-or-many items of the same type (like multiple alumniOf elements for a single Person?

If so, any pointer to the documentation?