Two boys looking at display.
The boys walk past the display.
Walking past a display contradicts with the boys specifically looking at the display.
exists e1 x1 x2.(at(e1,x2) & n_display(x2) & Actor(e1,x1) & v_look(e1) & n_boy(x1) & card_eq_2(x1))
exists e1 x1 x2.(n_display(x2) & n_boy(x1) & past(e1,x2) & Actor(e1,x1) & v_walk(e1))