A man on a motorcycle pops a wheelie in the dirt.
A man pops a wheelie on a motorcycle.
The man is riding a motorcycle so it can be assumed that when he is popping the wheelie it is on the motorcycle.
exists e1 x1 x2 x3 x4.(n_dirt(x4) & in(e1,x4) & Theme(e1,x3) & Actor(e1,x1) & v_pop(e1) & n_wheelie(x3) & on(x1,x2) & n_motorcycle(x2) & n_man(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_pop(e1) & on(x2,x3) & n_motorcycle(x3) & n_wheelie(x2) & n_man(x1))