《周书·列传·卷十》
九岁时，被命为虞凰公的嫡长子。
九岁，命为虞国公世子。
At nine, he was appointed the legitimate eldest son of Yuhuanggong.
<s>[INST] Rewrite the following English passage in the style of Classical Chinese: At nine, he was appointed the legitimate eldest son of Yuhuanggong. [/INST] 九岁，命为虞国公世子。</s>
Rewrite the following English passage in the style of Classical Chinese: At nine, he was appointed the legitimate eldest son of Yuhuanggong.
user
九岁，命为虞国公世子。
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