a man doing tricks on a bmx bike
A man runs a race
A man either runs a race or is doing tricks on a bike, he can not do both actions at the same time.
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & on(e1,x4) & n_bike(x4) & of(x4,x5) & n_bmx(x5) & Theme(e1,x3) & Actor(e1,x2) & v_do(e1) & n_trick(x3) & (x1 = x2) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_run(e1) & n_race(x2) & n_man(x1))