A black and white dog playing with a white ball in a sparse brown field.
A dog plays with his favorite ball.
Sentence two tells us that this ball isn't any old ball. It's the dog's favorite ball.
exists s1 s2 s3 s4 s5 x1 x2 x3 x4.(a_topic(x1) & with(x1,x3) & in(x3,x4) & n_field(x4) & a_brown(s5) & Theme(s5,x4) & a_sparse(s4) & Theme(s4,x4) & n_ball(x3) & a_white(s3) & Theme(s3,x3) & n_playing(x1) & of(x1,x2) & n_dog(x2) & a_white(s2) & Theme(s2,x1) & a_black(s1) & Theme(s1,x1))
exists e1 s1 x1 x2.(with(e1,x2) & n_ball(x2) & a_favorite(s1) & Theme(s1,x2) & of(x2,x1) & n_male(x1) & Actor(e1,x1) & v_play(e1) & n_dog(x1))