Maintain the natural curve in your lower back.

保持腰背部的自然弯曲。

youdao

Maintain the natural curve in your lower back, and don't hold your breath.

保持腰背部的自然弯曲，不要屏住呼吸。

youdao

Maintain the natural curve in your lower back, and keep your core muscles tight.

保持腰背部的自然弯曲，保持收紧你的核心肌肉。

youdao

Over time, it can even flatten or reverse the natural curve of your neck.

CNN: Your smartphone is a pain in the neck

The use case supposition is probably that the user will accessorize with a bluetooth headset, although the natural bluetooth headset usability decay curve means that it will eventually be abandoned for a wired headset or the speaker.

FORBES: Move up http://i.forbesimg.com t Move down

In economics, luxury goods have an inverse demand curve, Dale, with Wodka, is trying to turn it back to its natural position.

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