Two children are on the beach and are playing in the wet sand.
Two kids are at the beach.
You can not infer they are on the beach.
exists e1 p1 s1 x1 x2 x3 x4.(n_sand(x3) & a_wet(s1) & Theme(s1,x3) & n_beach(x4) & in(e1,x3) & Actor(e1,x2) & v_play(e1) & n_child(x2) & card_eq_2(x2) & on(x1,x4) & n_child(x1) & card_eq_2(x1))
exists p1 x1 x2.(n_beach(x2) & at(x1,x2) & n_kid(x1) & card_eq_2(x1))