A man sits on stairs with a woman.
a man and woman sit on the stairs
Both subjects sits
exists e1 x1 x2 x3.(with(e1,x3) & n_woman(x3) & on(e1,x2) & n_stair(x2) & Actor(e1,x1) & v_sit(e1) & n_man(x1))
exists e1 x1 x2 x3 x4.(n_stair(x4) & on(e1,x4) & Actor(e1,x1) & v_sit(e1) & n_woman(x3) & n_man(x2) & subset_of(x3,x1) & subset_of(x2,x1))