Two children sitting by the water.
Two girls are sitting by a lake.
not all children are girls..
exists e1 x1 x2 x3.(n_water(x3) & a_topic(x1) & by(e1,x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_child(x1) & card_eq_2(x1))
exists e1 x1 x2.(by(e1,x2) & n_lake(x2) & Actor(e1,x1) & v_sit(e1) & n_girl(x1) & card_eq_2(x1))