A gray dog is yawning.
A gray dog is sleeping.
A dog that is yawning cannot be sleeping same time.
exists e1 s1 x1.(Actor(e1,x1) & v_yawn(e1) & n_dog(x1) & a_gray(s1) & Theme(s1,x1))
exists e1 s1 x1.(Actor(e1,x1) & v_sleep(e1) & n_dog(x1) & a_gray(s1) & Theme(s1,x1))