《黄帝内经·素问·阴阳应象大论》
所以说： 阴阳是互相为用的，阴在内，为阳之镇守；阳在外，为阴之役使。 
故曰： 阴在内，阳之守也，阳在外，阴之使也。 
Therefore it is said: Yin and yang work together; yin is within and stabilizes yang; yang is without and puts yin to use.
<s>[INST] Render the following Classical Chinese text into fluent English: 故曰： 阴在内，阳之守也，阳在外，阴之使也。  [/INST] Therefore it is said: Yin and yang work together; yin is within and stabilizes yang; yang is without and puts yin to use.</s>
Render the following Classical Chinese text into fluent English: 故曰： 阴在内，阳之守也，阳在外，阴之使也。
user
Therefore it is said: Yin and yang work together; yin is within and stabilizes yang; yang is without and puts yin to use.
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