A wakeboarder is performing a trick on a rail.
He is on the water.
rail refers to one is on the water.
exists e1 x1 x2 x3.(on(e1,x3) & n_rail(x3) & Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_trick(x2) & n_wakeboarder(x1))
exists p1 x1 x2.(n_water(x2) & n_male(x1) & on(x1,x2))