Chin cup helps to position the facepiece properly.

下巴杯面罩有助于正确位置。

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Neck de-tenser Lie on your stomach, elbows on floor. With eyes closed, cup chin with your left palm and support the back of your head firmly with right hand.

放松颈部动作俯身卧倒，腹部着地，双肘着地，闭上双眼，左手掌呈杯状托着下巴，右手用力扶着头后部。

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Neck de-tenser4 Lie on your stomach, elbows on floor. With eyes closed, cup chin with your left palm and support the back of your head firmly with right hand.

放松颈部动作俯身卧倒，腹部着地，双肘着地，闭上双眼，左手掌呈杯状托着下巴，右手用力扶着头后部。

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The child lay on a tall padded table and placed his chin in a little cup.

NEWYORKER: Backbone