Two surgeons performing a surgery.
Doctors are working.
Surgeons are doctors. Performing a surgery is a doctor's form of work.
exists e1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_perform(e1) & n_surgery(x3) & (x1 = x2) & n_surgeon(x1) & card_eq_2(x1))
exists e1 x1.(Actor(e1,x1) & v_work(e1) & n_doctor(x1))