A man at work, butchering a cow.
A doctor prescribes medicine to a patient.
The man butchering a cow is not a doctor. He butchers a cow which is not prescribing medicine.
exists e1 x1 x2 x3 x4.(a_topic(x1) & Theme(e1,x4) & Actor(e1,x3) & v_butcher(e1) & n_cow(x4) & (x1 = x3) & at(x1,x2) & n_work(x2) & n_man(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_prescribe(e1) & to(x2,x3) & n_patient(x3) & n_medicine(x2) & n_doctor(x1))