A boy and woman sitting on a passenger train
a boy and woman
A boy and woman is same as a boy and woman
exists e1 s1 x1 x2 x3 x4 x5.(a_topic(s1) & on(e1,x4) & n_train(x4) & of(x4,x5) & n_passenger(x5) & Actor(e1,x3) & v_sit(e1) & (s1 = x3) & n_woman(x2) & n_boy(x1) & subset_of(x2,s1) & subset_of(x1,s1))
exists s1 x1 x2.(a_topic(s1) & subset_of(x2,s1) & n_woman(x2) & subset_of(x1,s1) & n_boy(x1))