《后汉书·列传·刘虞公孙瓚陶谦列传》
袁绍派部将崔巨业领兵数万围攻故安不下，退兵南归。
绍遣将崔巨业将兵数万攻围故安，不下，退军南还。
Yuan Shao sent his commander Cui Juye to besiege Gu’an for several months with ten thousand soldiers, but he retreated south when it proved unyielding.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 绍遣将崔巨业将兵数万攻围故安，不下，退军南还。 [/INST] Yuan Shao sent his commander Cui Juye to besiege Gu’an for several months with ten thousand soldiers, but he retreated south when it proved unyielding.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 绍遣将崔巨业将兵数万攻围故安，不下，退军南还。
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Yuan Shao sent his commander Cui Juye to besiege Gu’an for several months with ten thousand soldiers, but he retreated south when it proved unyielding.
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