《新唐书·列传·卷五十》
开元后，宰相不以姓著者，称之为 燕公 。
开元后，宰相不以姓著者，曰燕公云。
After the Kaiyuan era, the prime minister was not known by his surname, but was called Duke Yan.
<s>[INST] 请将下面的文言文翻译成英语: 开元后，宰相不以姓著者，曰燕公云。 [/INST] After the Kaiyuan era, the prime minister was not known by his surname, but was called Duke Yan.</s>
请将下面的文言文翻译成英语: 开元后，宰相不以姓著者，曰燕公云。
user
After the Kaiyuan era, the prime minister was not known by his surname, but was called Duke Yan.
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