A restaurant worker is cleaning a seat.
A bus-boy cleaning
It cannot be determined that the restaurant worker is a bus-boy.
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_clean(e1) & n_seat(x3) & n_worker(x1) & of(x1,x2) & n_restaurant(x2))
exists s1 x1.(a_topic(x1) & n_cleaning(x1) & a_bus-boy(s1) & Theme(s1,x1))