A man stands over a brown and black dog in the grass.
A dog is playing outside with its owner.
The first sentence only says the man and dog are in the grass.  It doesn't say the man is the owner, nor does it say what else they are doing.  I can't infer that they are outside playing.
exists e1 s1 s2 x1 x2 x3.(n_grass(x3) & in(e1,x3) & over(e1,x2) & n_dog(x2) & a_black(s2) & Theme(s2,x2) & a_brown(s1) & Theme(s1,x2) & Actor(e1,x1) & v_stand(e1) & n_man(x1))
exists e1 x1 x2.(with(e1,x2) & n_owner(x2) & of(x2,x1) & n_thing(x1) & r_outside(e1) & Actor(e1,x1) & v_play(e1) & n_dog(x1))