For example a Professor is a Person and also a University Employee or a Person who is not a Student. The same can be expressed in First Order Logic. If X is a Professor it holds for all X, then X is also a Person and a University Employee or a Person and not a Student.
Professor ⊑ (Person ⊓ UniversityEmployee) ⊓ (Person ⊓ ¬Student)
(∀x)(Professor(x) → ((Person Λ UniversityEmployee(x)) V (Person(x) Λ ¬Student(x)))