The dog is carrying a toy through the grass.
The dog was playing in the grass.
Just because the dog is carrying a toy through the grass does not mean the dog is playing.
exists e1 x1 x2 x3.(n_grass(x3) & n_dog(x1) & through(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_carry(e1) & n_toy(x2))
exists e1 x1 x2.(n_grass(x2) & n_dog(x1) & in(e1,x2) & Actor(e1,x1) & v_play(e1))