《后汉书·本纪·光武帝纪下》
五月二十八日，帝从长安回洛阳。
五月乙丑，至自长安。
On the 28th day of the 5th month, the emperor returned to Luoyang from Chang'an.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 五月乙丑，至自长安。 [/INST] On the 28th day of the 5th month, the emperor returned to Luoyang from Chang'an.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 五月乙丑，至自长安。
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On the 28th day of the 5th month, the emperor returned to Luoyang from Chang'an.
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