Red blood cells carry oxygen, and a shortage of those will cause fatigue and shortness of breath.

红细胞具有携氧功能，红细胞缺乏会引起呼吸急促和疲乏。

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Red blood cells carry oxygen, and a shortage of those will cause fatigue and shortness of breath.

红细胞具有携氧功能，红细胞缺乏会引起呼吸急促和疲乏。

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