The cow needs the dog. The cow sees the dog. The dog eats the cow. The dog is green. The dog is round. The dog needs the cow. The dog sees the cow. If the cow eats the dog then the cow needs the dog. If something eats the dog then the dog is young. If the cow is round then the cow needs the dog. If the dog sees the cow then the cow sees the dog. If the cow is young then the cow sees the dog. If something sees the cow and the cow eats the dog then the dog eats the cow. If something needs the dog and it needs the cow then the cow is nice. If something is round and it needs the cow then it eats the dog.
The cow does not need the dog.