《元史·本纪·卷十六》
十二日，把奉先县改为房山县。
丙戌，改奉先县为房山县。
On the twelfth day, Fengxian County was changed to Fangshan County.
<s>[INST] Convert the following English text into Classical Chinese: On the twelfth day, Fengxian County was changed to Fangshan County. [/INST] 丙戌，改奉先县为房山县。</s>
Convert the following English text into Classical Chinese: On the twelfth day, Fengxian County was changed to Fangshan County.
user
丙戌，改奉先县为房山县。
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