How to add a label to multi-value fields in LDAP

I think there is everything in the title but let me make an example to be more clear.

Let's take the mail attribute. It's a multi value attribute so I can store more than one email in there but how can I label each item with info like "work mail" "personal mail" and so on?

Thank you!

I don't think you can since its values are unordered. The only thing what comes to my mind is to pre- or suffix it.
office:mail@company.com private:mail@private.com
And then split it where you're using it (Script/Code).
Or just use multible attributes like: mail, privatemail, ...