A couple walking on a dirt road.
Two people are riding dirt bikes.
The couple cannot be walking and riding bikes simultaneously.
exists e1 x1 x2 x3 x4.(a_topic(x1) & on(e1,x3) & n_road(x3) & of(x3,x4) & n_dirt(x4) & Actor(e1,x2) & v_walk(e1) & (x1 = x2) & n_couple(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2) & of(x2,x3) & n_dirt(x3) & n_people(x1) & card_eq_2(x1))