The boy swings next to the barn.
A girl is playing in the sand.
One cannot be both a boy and a girl.
exists e1 x1 x2.(n_barn(x2) & n_boy(x1) & to(e1,x2) & r_next(e1) & Actor(e1,x1) & v_swing(e1))
exists e1 x1 x2.(n_sand(x2) & in(e1,x2) & Actor(e1,x1) & v_play(e1) & n_girl(x1))