A greyhound racing.
A dog is running.
Greyhound is a dog, it must run in order to race
exists s1 x1.(a_topic(x1) & n_racing(x1) & a_greyhound(s1) & Theme(s1,x1))
exists e1 x1.(Actor(e1,x1) & v_run(e1) & n_dog(x1))