Besides underpropping comfortably and reducing temperature of skin during sleeping, it can also promote the blood circulation and promote deep sleeping.

睡眠中，提供符合人体工学的支撑，降低皮肤温度，促进血液循环效率，促进深度睡眠。

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Baby will spend two-thirds time in deep sleeping, so a good pillow can not only help baby in a deep sleep, but also protect the baby and his dedicated head.

婴幼儿三分之二的时间在睡眠中度过，一款好的枕头，不仅可以帮助宝宝进入深度睡眠，同时还可以呵护宝宝娇嫩的头形。

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Sleeping deep underwater helps these seals stay safe from animals that hunt them near the surface.

沉睡在水下可以帮助这些海豹远离在水面附近捕猎它们的动物。

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Their study shows that as young people grow older they spend less of their sleeping time in slow wave or deep sleep.

BBC: Sleep linked to ageing