Over time, if your blood doesn't circulate enough oxygen throughout your body, your lips and fingernails can take on a blue or gray tone.

随着时间过去，如果你的血液没能将足够的氧气循环到全身，你的唇和手指甲会呈现蓝色或灰色调。

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GP suggested that Kaylee was suffering from a bad cold, but within 24 hours her lips turned blue.

一位全科医师推断凯莉患了严重的感冒，但在24小时内，她的嘴唇开始发青。

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She was sitting in the tub shivering, and her lips were blue.

她站在浴缸里发抖，嘴唇是蓝色的。

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Her thin little face, which had used to look creamy, was peaky, blue around the lips.

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He said he could see that she was injured and "had gone very pale, her lips were blue".

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To be honest, I didn't think he would survive, his lips were blue.

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