Children playing checkers.
Children compete in a checkers tournament.
From sentence 1 it cannot be inferred that the children are in a checkers tournament.
exists e1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_play(e1) & n_checkers(x3) & (x1 = x2) & n_child(x1))
exists e1 x1 x2 x3.(in(e1,x2) & n_tournament(x2) & of(x2,x3) & n_checkers(x3) & Actor(e1,x1) & v_compete(e1) & n_child(x1))