Shift weight and roll back to balance on sit bones.

移动体重，向后滚动，在坐骨上维持平衡。

youdao

Any mention of a problem with the house these days made Dad smile his Mr. Bones smile and roll his eyes.

NEWYORKER: Mr. Bones

Five years down the line you are going to get bones breaking or to put it simply you roll over in bed and break a hip.

BBC: Acid 'cuts prostate cancer patients' fractures'