Which film editor did M1 employ , M2 employ , M3 employ , and M4 employ
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:film.editor .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M4
}