A man is firing a handgun.
A handgun is being fired by a man.
In order for a handgun to be fired the man must fire it.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_fire(e1) & n_handgun(x2) & n_man(x1))
exists e1 x1 x2.(Actor(e1,x2) & n_man(x2) & Theme(e1,x1) & v_fire(e1) & n_handgun(x1))