A boy is doing a skateboarding trick in the air.
A boy is riding a skateboard.
You have to be riding a skateboard in order to do a trick
exists e1 e2 x1 x2 x3.(n_air(x3) & Theme(e2,x2) & Actor(e2,x1) & v_do(e2) & in(x2,x3) & n_trick(x2) & Actor(e1,x2) & v_skateboard(e1) & n_boy(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_skateboard(x2) & n_boy(x1))