A dog shows his teeth while playing with another dog.
The dog is barking.
Playing and barking are different.
exists e2 e1 x1 x2 x3.(while(e1,e2) & with(e2,x3) & n_dog(x3) & -(x3 = x1) & n_dog(x1) & n_dog(x1) & Actor(e2,x1) & v_play(e2) & Theme(e1,x2) & Actor(e1,x1) & v_show(e1) & n_tooth(x2) & of(x2,x1) & n_male(x1))
exists e1 x1.(n_dog(x1) & Actor(e1,x1) & v_bark(e1))