Bob is big. Bob is blue. Bob is green. Dave is furry. Harry is blue. Harry is rough. Harry is young. All furry, big things are not quiet. Young, big things are blue. If something is big and not quiet then it is blue. All rough, quiet things are not young. If Dave is blue and Dave is furry then Dave is big. If Dave is quiet and Dave is not blue then Dave is not young. If Dave is green and Dave is not blue then Dave is furry. If something is blue and not furry then it is young.
Harry is not green.