People are walking past one another.
Men and women greet each other on the street.
There is no evidence these people are both men and women. It might be all men walking past one another. You also can't assume they greet each other when they walk past each other.
exists e1 s1 x1 x2.(past(e1,x2) & n_thing(x2) & card_eq_1(x2) & a_another(s1) & Theme(s1,x2) & Actor(e1,x1) & v_walk(e1) & n_people(x1))
exists x1 x2 x3 x5.(n_street(x5) & all x4.(n_other(x4) -> exists e1.(on(e1,x5) & Theme(e1,x4) & Actor(e1,x1) & v_greet(e1))) & subset_of(x3,x1) & n_woman(x3) & subset_of(x2,x1) & n_man(x2))