question: Was M1 employed by M2 , M3 , and M4 , employed by a screenwriter 's employer , and employed by M5
query: SELECT count(*) WHERE {
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x1 .
  ?x1 a ns:film.writer .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M4 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M5
  }