An adult and child walking along the beach on the sand.
the child is at the beach
The child is walking along the beach, meaning it is at said beach.
exists s1 x1 x2 x3 x4 x5.(n_sand(x5) & n_beach(x4) & a_topic(s1) & along(s1,x4) & on(x4,x5) & subset_of(x2,s1) & n_walking(x2) & of(x2,x3) & n_child(x3) & subset_of(x1,s1) & n_adult(x1))
exists p1 x1 x2.(n_beach(x2) & n_child(x1) & at(x1,x2))