肺细胞约每周新老更替一次。Lung cells die and are replaced about once a week.肺实际上由上千条细微的气管构成。The lungs are in fact constructed of thousands of tiny tubes.肺呼出这些废气被排到空气中。As the lungs exhale this waste, gas is expelled into the atmospher...

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“肺”的拼音为：fèi...