A boy is riding his bike over a ramp at a park.
A child is doing a pop-a-wheelie on his bike.
We have no idea if the child is doing a pop-a-wheelie on his bike, he could be doing anything off the ramp.
exists e1 x1 x2 x3 x4.(at(e1,x4) & n_park(x4) & over(e1,x3) & n_ramp(x3) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2) & of(x2,x1) & n_male(x1) & n_boy(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & on(x2,x3) & n_bike(x3) & of(x3,x1) & n_male(x1) & n_pop-a-wheelie(x2) & n_child(x1))