Running water is never stale and a door-hinge never gets worm-eaten.

流水不腐，户枢不蠹。

《新英汉大辞典》

"Running water is never stale and a door-hinge is never worm-eaten" means that constant motion prevents the inroads of germs and other organisms.

“流水不腐，户枢不蠹”，是说它们在不停的运动中抵抗了微生物或其他生物的侵蚀。

youdao

The company currently product system is divided into flat open doors and Windows of hand, flat open door hinge, flat open doors and Windows clutch, flat open lock products and zero accessories.

公司目前产品体系分为平开门窗执手、平开门窗铰链、平开门窗传动器、平开门锁等产品及其零附件。

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One neat trick: The right-side passenger door can hinge conventionally or backward, so people getting into the back of the car have easier access.

FORBES: Vehicles Feature

Opening the rear door reveals a rear-hinged configuration, with a single, oversized, brushed-aluminum hinge articulating diagonally from the rear door cutline.

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