Bob is not big. Bob is green. Bob is nice. Charlie is not rough. Charlie is not smart. Dave is rough. Erin is nice. If something is big and round then it is smart. All rough, big things are not young. All round things are rough. Big, smart things are rough. If something is round and big then it is not green. If something is young and big then it is not round. Round, big things are young. If something is not rough and not green then it is not big.
Dave is not young.