Four dirt bike riders are riding on a dirt road.
Four dirt bike riders race one another along a dirt road.
The riders may not be part of a race.
exists e1 x1 x2 x3 x4 x5.(on(e1,x4) & n_road(x4) & of(x4,x5) & n_dirt(x5) & Actor(e1,x1) & v_ride(e1) & n_rider(x1) & of(x1,x3) & n_bike(x3) & of(x1,x2) & n_dirt(x2) & card_eq_4(x1))
exists s1 x1 x2 x3 x4 x5 x6.(a_topic(x1) & along(x1,x5) & n_road(x5) & of(x5,x6) & n_dirt(x6) & n_race(x1) & card_eq_1(x1) & a_another(s1) & Theme(s1,x1) & of(x1,x4) & n_rider(x4) & of(x1,x3) & n_bike(x3) & of(x1,x2) & n_dirt(x2) & card_eq_4(x1))