question: What was acquired by M0 and M1 , acquired by M4 's employer , acquired by M2 , and acquired by M3
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x1 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M0 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M1 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M2 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M3 .
  ?x1 ns:business.employer.employees/ns:business.employment_tenure.person M4
  }