《资治通鉴·汉纪·汉纪三十》
十二月三十日，军队秘密行动，乘夜出发，攻取兰乡，把甄阜军的物资全部夺获。
十二月，晦，潜师夜起，袭取蓝乡，尽获其辎重。
On the thirtieth day of December, the army acted in secret, setting out at night, captured Lanxiang, and seized all the supplies of the Zhen Fuchun army.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 十二月，晦，潜师夜起，袭取蓝乡，尽获其辎重。 [/INST] On the thirtieth day of December, the army acted in secret, setting out at night, captured Lanxiang, and seized all the supplies of the Zhen Fuchun army.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 十二月，晦，潜师夜起，袭取蓝乡，尽获其辎重。
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On the thirtieth day of December, the army acted in secret, setting out at night, captured Lanxiang, and seized all the supplies of the Zhen Fuchun army.
assistant