Biker doing a trick in air.
The biker is doing tricks
The biker who is doing a trick is the same as a bike is doing tricks
exists e1 x1 x2 x3.(ne_nam_biker(x1) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & in(x2,x3) & n_air(x3) & n_trick(x2))
exists e1 x1 x2.(n_biker(x1) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_trick(x2))