A BMX rider on the trail.
Someone is riding a BMX bike down a dirt path
One cannot assume that the biker is going down a dirt path.
exists x1 x2 x3.(n_trail(x3) & a_topic(x1) & on(x1,x3) & n_rider(x1) & (x1 = x2) & ne_org_bmx(x2))
exists e1 x1 x2 x3 x4 x5.(down(e1,x4) & n_path(x4) & of(x4,x5) & n_dirt(x5) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2) & (x2 = x3) & ne_org_bmx(x3) & n_person(x1))