《旧唐书·列传·卷一百二十四》
因此我修养身心一千二百岁了，形体从未衰老。 
故我修身千二百岁矣，吾形未尝衰。 
Therefore, I have cultivated my body, spirit, and mind for twelve hundred years, and my form has never grown old.
<s>[INST] Convert the following modern Chinese text into Classical Chinese: 因此我修养身心一千二百岁了，形体从未衰老。  [/INST] 故我修身千二百岁矣，吾形未尝衰。 </s>
Convert the following modern Chinese text into Classical Chinese: 因此我修养身心一千二百岁了，形体从未衰老。
user
故我修身千二百岁矣，吾形未尝衰。
assistant