“斑”怎么读？

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牙斑如果不清除就会导致牙齿蛀蚀和牙龈疾病。When not removed, plaque causes tooth decay and gum disease.戒指内侧有一层厚厚的锈斑。The tarnish lay thick on the inside of the ring.她比较胖，脸色暗淡、多斑。She was rather fat, and her complexion was muddy and spotty....