At the early morning of winter, to leave the warm sleeping bag, this is really a painful and helpless thing.

在冬天的清晨，离开我温暖的被窝，是一件很痛苦很无奈的事情。

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This sleeping bag is very warm.

这条睡袋很暖和。

《牛津词典》

Modern sleeping bag lets you keep warm without being restricted.

现代睡衣式睡袋，让你不受拘束就能轻松保暖。

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Inside, keep your body off the ice or ground (the Inuit put their sleeping blankets on top of a bed of sticks and reeds) and create heat-trapping "loft" (it's what keeps you warm in a sleeping bag) by layering a few small blankets or big trash bags, with leaves or crumpled newspapers in between.

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