The dog chases the mouse. The dog is big. The dog is blue. The dog is not green. The dog is rough. The dog is young. The dog needs the mouse. The dog sees the mouse. The mouse chases the dog. The mouse is blue. The mouse is green. The mouse is rough. The mouse is not young. The mouse needs the dog. The mouse does not see the dog. If something needs the mouse and the mouse is not young then the mouse needs the dog.
The mouse chases the mouse.