Two motocross riders next to each other on a dirt track.
people on motorbikes
Two motocross riders next to each other on a dirt track means there are people on motorbikes.
exists s1 x1 x2 x3 x4 x5.(a_topic(x1) & on(x1,x4) & n_track(x4) & of(x4,x5) & n_dirt(x5) & all x6.(n_other(x6) -> to(s1,x6)) & Theme(s1,x3) & a_next(s1) & (x1 = x3) & n_rider(x1) & of(x1,x2) & n_motocross(x2) & card_eq_2(x1))
exists x1 x2.(a_topic(x1) & on(x1,x2) & n_motorbike(x2) & n_people(x1))