A child on a swing.
A child plays alone on a swing.
A child on a swing does not imply that the child is playing alone on a swing.
exists x1 x2.(a_topic(x1) & on(x1,x2) & n_swing(x2) & n_child(x1))
exists e1 s1 x1 x2.(a_alone(s1) & Manner(e1,s1) & on(e1,x2) & n_swing(x2) & Actor(e1,x1) & v_play(e1) & n_child(x1))