person := {student ; employee}.
employee := {staff ; faculty}.
workstudy <| student.
workstudy <| staff.

bob    <| student.
piotr  <| student.
pablo  <| student.
elena  <| workstudy.
simon  <| workstudy.
art    <| staff.
judy   <| staff.
don    <| faculty.
john   <| faculty.
sheila <| faculty.

stu -> X:student(advisor  => faculty(secretary => Y:staff,
                                     assistant => X),
                 roommate => employee(representative => Y)).

emp -> employee(advisor  => don(secretary => elena,
                                             assistant => U : student),
                roommate => V:student(representative => V),
                helper   => simon(spouse => U)).
