Choose a chair that supports your back, including the curve in your lower back (if not, place a rolled up towel or pillow behind your lower back for support).

找把能靠背的椅子，椅背曲线要与自己的背部贴合，或者在你的背后卷条毛巾或放个枕头。

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Using a pillow placed against the small of your back can provide additional support as well.

FORBES: Five Tips to Reduce Neck and Shoulder Pain When Using a Tablet or Computer