Nesech-wine is prohibited, and it prohibits [that with which it mixes] by the smallest quantity. Wine in wine or water in water [prohibits the mixture] by the smallest quantity. Wine in water or water in wine [prohibits only] if it imparts flavor. This is the rule: A [prohibited] substance [which mixes] into [a permitted substance of] the same kind [prohibits] by the smallest quan-tity; but [if it mixes] into [a substance of] a different kind [it prohibits only] if it imparts flavor.