Two children walking on a platform.
Three kids sitting on a bed.
One cannot be sitting and walking at the same time.
exists e1 x1 x2 x3.(a_topic(x1) & on(e1,x3) & n_platform(x3) & Actor(e1,x2) & v_walk(e1) & (x1 = x2) & n_child(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(a_topic(x1) & on(e1,x3) & n_bed(x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_kid(x1) & card_eq_3(x1))