A man on a motorcycle is racing on a track.
There is a vehicle racing on the track.
Motorcycle is a vehicle.
exists e1 x1 x2 x3.(on(e1,x3) & n_track(x3) & Actor(e1,x1) & v_race(e1) & on(x1,x2) & n_motorcycle(x2) & n_man(x1))
exists p1 x1 x4.(n_track(x4) & exists x2 x3.((x1 = x2) & on(x2,x4) & n_racing(x2) & of(x2,x3) & n_vehicle(x3)))