Use your hand to power the hoop in a back-and-forth motion: the hoop will alternate between hitting the center of your palm and the back of your hand.

用你的手来给呼啦圈前后移动的力：呼啦圈会在你的手掌心和手背上交替着力。

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Instead of trying to figure out your motion patterns, Gentle Alarm takes a statistical approach: near the end of the night, light sleep and deep sleep alternate every 30 minutes or so.

因此，Gentle Alarm并非通过您的动作来测算您的睡眠状态，而是根据的统计结果：在夜幕即将结束的时候，浅睡眠阶段与深睡眠阶段约每30分钟交替一次。

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