《北史·列传·卷三》
皇帝又对群臣们说： 以前平文皇帝去世，昭成皇帝营建盛乐。
帝又诏群臣曰： 昔平文皇帝弃背，昭成营居盛乐。
The emperor said to his courtiers: In the past, Emperor Pingwen passed away, and Emperor Zhaocheng built Shengle.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 帝又诏群臣曰： 昔平文皇帝弃背，昭成营居盛乐。 [/INST] The emperor said to his courtiers: In the past, Emperor Pingwen passed away, and Emperor Zhaocheng built Shengle.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 帝又诏群臣曰： 昔平文皇帝弃背，昭成营居盛乐。
user
The emperor said to his courtiers: In the past, Emperor Pingwen passed away, and Emperor Zhaocheng built Shengle.
assistant