two people are looking off a cliff.
Two people are standing at an edge.
To be looking off a cliff is to be standing at an edge.
exists e1 x1 x2.(off(e1,x2) & n_cliff(x2) & Actor(e1,x1) & v_look(e1) & n_people(x1) & card_eq_2(x1))
exists e1 x1 x2.(at(e1,x2) & n_edge(x2) & Actor(e1,x1) & v_stand(e1) & n_people(x1) & card_eq_2(x1))