Motorcyclists racing on a track.
People are racing.
Motorcyclists racing means people are racing
exists e1 x1 x2 x3.(a_topic(x1) & on(e1,x3) & n_track(x3) & Actor(e1,x2) & v_race(e1) & (x1 = x2) & n_motorcyclist(x1))
exists e1 x1.(Actor(e1,x1) & v_race(e1) & n_people(x1))