Man and woman fishing in the ocean.
Man and woman fishing in a small river in the mountains.
An ocean is different from a small river.
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 s2 x1 x2 x3 x4 x5.(n_mountain(x5) & a_topic(s1) & subset_of(x2,s1) & in(x2,x4) & in(x4,x5) & n_river(x4) & a_small(s2) & Theme(s2,x4) & n_fishing(x2) & of(x2,x3) & n_woman(x3) & subset_of(x1,s1) & n_man(x1))