A traffic controller is watching his camera.
The controller is taking a nap.
The controller watching his camera cannot be taking a nap.
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_watch(e1) & n_camera(x3) & of(x3,x1) & n_male(x1) & n_controller(x1) & of(x1,x2) & n_traffic(x2))
exists e1 x1 x2.(n_controller(x1) & Theme(e1,x2) & Actor(e1,x1) & v_take(e1) & n_nap(x2))