A man doing an aerial stunt on a bike.
A biker performs a trick.
A man on a bike is a biker, and a stunt on a bike is also termed a trick.
exists e1 s1 x1 x2 x3 x4.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_do(e1) & on(x3,x4) & n_bike(x4) & n_stunt(x3) & a_aerial(s1) & Theme(s1,x3) & (x1 = x2) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_trick(x2) & n_biker(x1))