premise: Two doctors perform surgery on patient.
hypothesis: Two surgeons are having lunch.
explanation_1: The subjects cannot perform surgery and be having lunch simultaneously.
explanation_2: The doctors/surgeons can perform surgery or be said to be having lunch but not both at the same time.
explanation_3: perform surgery  is different from having lunch.
premise_logic: exists e1 x1 x2 x3.(on(e1,x3) & n_patient(x3) & Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_surgery(x2) & n_doctor(x1) & card_eq_2(x1))
hypothesis_logic: exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & n_lunch(x2) & n_surgeon(x1) & card_eq_2(x1))