Man and woman fishing in the ocean.
Man and woman fishing for buffalo.
They are either fishing in the ocean or they are fishing for buffalo, but not both.
exists s1 x1 x2 x3 x4.(n_ocean(x4) & a_topic(s1) & subset_of(x2,s1) & in(x2,x4) & n_fishing(x2) & of(x2,x3) & n_woman(x3) & subset_of(x1,s1) & n_man(x1))
exists s1 x1 x2 x3 x4.(a_topic(s1) & subset_of(x2,s1) & for(x2,x4) & n_buffalo(x4) & n_fishing(x2) & of(x2,x3) & n_woman(x3) & subset_of(x1,s1) & n_man(x1))