A little girl and boy play in the sand on the beach.
The kids playing on the beach are building a sand castle
Kids can play in the sand and not be building anything such as a sand castle.
exists s1 s2 x1 x2 x3 x4 x5.(n_beach(x5) & n_sand(x4) & a_topic(s1) & in(s1,x4) & on(x4,x5) & n_play(x2) & of(x2,x3) & n_boy(x3) & n_girl(x1) & subset_of(x2,s1) & subset_of(x1,s1) & a_little(s2) & Theme(s2,s1))
exists e1 e2 x1 x2 x3 x4 x5.(n_beach(x3) & n_kid(x1) & Theme(e2,x4) & Actor(e2,x1) & v_build(e2) & n_castle(x4) & of(x4,x5) & n_sand(x5) & on(e1,x3) & Actor(e1,x2) & v_play(e1) & (x1 = x2))