To get the feel of proper diaphragmatic breathing, wear loose clothing and lie on the back.

为了感觉正确的腹隔膜式呼吸的呼吸，穿着宽松的衣服，躺在地上。

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"Bad sleep" means unease sleep, having two meanings: can not lie on the back, and can't sleep well.

卧不安“即不安卧之谓，更含两重意义，不能平卧与虽卧不安两者皆属。”

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Peek-a-boo (lower back): Lie face down on the floor using your outstretched arms to support baby in front of you.

躲猫猫（锻炼后腰）：脸朝下，用你伸展的胳膊支撑住你前面的婴儿。

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He would stand on tiptoe, bend double, lie on the ground, on his back or his stomach, take pan shots, medium shots, closeups, tracking shots, and panoramic shots, from above and from below, full face, from the side, from behind.

NEWYORKER: While the Women Are Sleeping

They would make him lie on his back looking up at the racing clouds while they tortured him in ways he could actually take.

NEWYORKER: Tenth of December

In Prague, my friend showed me something I will not forget: he got me to lie on my back and peer at the underside of some piece of ambassadorial furniture.

NEWYORKER: Broken Record