A man is smoking at sunset.
A man eating.
If the man is smoking then he is not eating.
exists e1 x1 x2.(at(e1,x2) & n_sunset(x2) & Actor(e1,x1) & v_smoke(e1) & n_man(x1))
exists x1 x2.(a_topic(x1) & n_eating(x1) & of(x1,x2) & n_man(x2))