A woman runs on a trail in nature.
A man runs on a trail in nature.
You can have either a woman or a man.
exists e1 x1 x2 x3.(in(e1,x3) & n_nature(x3) & on(e1,x2) & n_trail(x2) & Actor(e1,x1) & v_run(e1) & n_woman(x1))
exists e1 x1 x2 x3.(in(e1,x3) & n_nature(x3) & on(e1,x2) & n_trail(x2) & Actor(e1,x1) & v_run(e1) & n_man(x1))