我坐着的姿势难受极了。

I was sitting in an extremely uncomfortable position.

《牛津词典》

坐着的姿势是静止的、被动的，不活跃的。

The sitting position is motionless, passive, and inactive.

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姿势指的是一个人保持身体的方式，尤其是站立、行走或坐着时的背部、肩膀和头部。

Posture means the way in which someone holds his or her body, especially the back, shoulders and head when standing, walking, or sitting.

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