Dave is green. Erin is not quiet. Erin is red. Gary is big. Gary is red. Gary is rough. Harry is quiet. All rough people are big. If someone is green then they are quiet. If Harry is green then Harry is red. If someone is quiet then they are nice. If someone is red and big then they are nice. If someone is nice and green then they are blue. Blue people are rough.
Dave is not green.