A person in a blue biking uniform is ridding a dirt bike on a grassy track.
The person is in a race.
The person on the bike could be training or just having fun instead of being in a race.
exists e1 s1 s2 x1 x2 x3 x4 x5 x6.(Theme(e1,x4) & Actor(e1,x1) & v_rid(e1) & on(x4,x6) & n_track(x6) & a_grassy(s2) & Theme(s2,x6) & n_bike(x4) & of(x4,x5) & n_dirt(x5) & in(x1,x2) & n_uniform(x2) & of(x2,x3) & n_biking(x3) & a_blue(s1) & Theme(s1,x2) & n_person(x1))
exists p1 x1.(n_person(x1) & exists x2.(in(x1,x2) & n_race(x2)))