《金史·列传·卷十八》
高丽入侵，金兵守卫要塞，高丽没有攻进来，于是罢兵回国。
高丽入寇，以我兵屯守要害，不得进，乃还。
Goryeo invaded and the Jin troops defended the fortress. Goryeo did not capture the city, so they retreated and returned to their country.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 高丽入寇，以我兵屯守要害，不得进，乃还。 [/INST] Goryeo invaded and the Jin troops defended the fortress. Goryeo did not capture the city, so they retreated and returned to their country.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 高丽入寇，以我兵屯守要害，不得进，乃还。
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Goryeo invaded and the Jin troops defended the fortress. Goryeo did not capture the city, so they retreated and returned to their country.
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