《北史·列传·卷七》
后来灵太后让元愉的四个儿子都附属皇室本籍中，并追封元愉为临洮王。
后灵太后令愉之四子皆附属籍，追封愉临洮王。
Later, Ling Taihou asked Yuan Yu's four sons to belong to the royal family and posthumously named Yuan Yu as King of Lintao.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 后灵太后令愉之四子皆附属籍，追封愉临洮王。 [/INST] Later, Ling Taihou asked Yuan Yu's four sons to belong to the royal family and posthumously named Yuan Yu as King of Lintao.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 后灵太后令愉之四子皆附属籍，追封愉临洮王。
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Later, Ling Taihou asked Yuan Yu's four sons to belong to the royal family and posthumously named Yuan Yu as King of Lintao.
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