a boy performs a stunt on a BMX bike.
He is riding a bike.
A boy is riding a bike whilst performing a stunt.
exists e1 x1 x2 x3 x4.(on(e1,x3) & n_bike(x3) & (x3 = x4) & ne_org_bmx(x4) & Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_stunt(x2) & n_boy(x1))
exists e1 x1 x2.(n_male(x1) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2))