The concave groove, and some people even extends to the cheek. Due to the depression of lacrimal sulcus and surrounding skin of comparison and contrast, cause.

凹沟，有的人甚至可延伸到脸颊。由于泪沟的凹陷与周围皮肤的对比映衬，使下。

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Each time we use a facial muscle, a groove forms beneath the surface of the skin, which is why we see lines form with each facial expression.

每当你使用面部肌肉的时候，皮肤下就会形成一道凹槽，这就是你作表情的时候，脸部出现线条的原因。

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Chewing gum to muscle contraction, adjusting the facial skin, wrinkles gradually reduce the depth of groove formation, or even eliminate some small wrinkles.

咀嚼口香糖能收缩肌肉，调整脸部肌肤，逐渐减少皱纹沟形成的深度，甚至可以消除一些细小的皱纹。

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