A woman and a child play on a tire staircase
A woman and a boy are playing in a sandbox.
A child does not have to be a boy.  If a woman and child play on a tire staircase they are not in a sandbox.
exists s1 x1 x2 x3 x4 x5.(a_topic(s1) & subset_of(x2,s1) & on(x2,x4) & n_staircase(x4) & of(x4,x5) & n_tire(x5) & n_play(x2) & of(x2,x3) & n_child(x3) & subset_of(x1,s1) & n_woman(x1))
exists e1 x1 x2 x3 x4.(in(e1,x4) & n_sandbox(x4) & Actor(e1,x1) & v_play(e1) & subset_of(x3,x1) & n_boy(x3) & subset_of(x2,x1) & n_woman(x2))