《水经注·卷二十二》
城南就是长堤，是原来清水北岸的堤防。西边面对桐丘，城就是按此丘而取名的，城形呈斜长状，而不方正。洧水又往东流经新汲县旧城北边。
俗名之曰堤，其城南即长堤，固洧水之北防也。西面桐丘，其城邪长而不方，盖凭丘之称，即城之名矣。洧水又东径新汲县故城北。
The long dike to the south of the city is the dike on the north bank of the original Qing Shui. To the west is Tongqiu, and the city was named after this hill, the city is shaped like an oblique long shape, not square. The Weishui flows eastward again through the north of the old city of Xinji County.
<s>[INST] Kindly elucidate the central themes in this passage in English: 俗名之曰堤，其城南即长堤，固洧水之北防也。西面桐丘，其城邪长而不方，盖凭丘之称，即城之名矣。洧水又东径新汲县故城北。 [/INST] The long dike to the south of the city is the dike on the north bank of the original Qing Shui. To the west is Tongqiu, and the city was named after this hill, the city is shaped like an oblique long shape, not square. The Weishui flows eastward again through the north of the old city of Xinji County.</s>
Kindly elucidate the central themes in this passage in English: 俗名之曰堤，其城南即长堤，固洧水之北防也。西面桐丘，其城邪长而不方，盖凭丘之称，即城之名矣。洧水又东径新汲县故城北。
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The long dike to the south of the city is the dike on the north bank of the original Qing Shui. To the west is Tongqiu, and the city was named after this hill, the city is shaped like an oblique long shape, not square. The Weishui flows eastward again through the north of the old city of Xinji County.
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