A dirt biker leaps through the air.
The biker is performing tricks.
Just because a dirt biker jumps through the air does not mean that he is performing tricks.
exists e1 x1 x2 x3.(n_air(x3) & through(e1,x3) & Actor(e1,x1) & v_leap(e1) & n_biker(x1) & of(x1,x2) & n_dirt(x2))
exists e1 x1 x2.(n_biker(x1) & Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_trick(x2))