《资治通鉴·唐纪·唐纪二十八》
酒酣之际，玄宗对张说说： 朕以往曾多次派使臣分巡各道考察地方官的善恶，这次由于封禅而得以亲自到各州走一走，才发现使臣们辜负朕的地方太多了。
酒酣，上谓张说曰： 向者屡遣使臣分巡诸道，察吏善恶，今因封禅历诸州，乃知使臣负我多矣。
When the wine was in full swing, Emperor Xuanzong said to Zhang Shuo: "In the past, I sent envoys to inspect the good and evil of local officials in various provinces several times, but this time, I was able to visit various states in person due to the ceremony of conferring titles. I found that the envoys had failed me in many places.
<s>[INST] Kindly elucidate the central themes in this passage in English: 酒酣，上谓张说曰： 向者屡遣使臣分巡诸道，察吏善恶，今因封禅历诸州，乃知使臣负我多矣。 [/INST] When the wine was in full swing, Emperor Xuanzong said to Zhang Shuo: "In the past, I sent envoys to inspect the good and evil of local officials in various provinces several times, but this time, I was able to visit various states in person due to the ceremony of conferring titles. I found that the envoys had failed me in many places.</s>
Kindly elucidate the central themes in this passage in English: 酒酣，上谓张说曰： 向者屡遣使臣分巡诸道，察吏善恶，今因封禅历诸州，乃知使臣负我多矣。
user
When the wine was in full swing, Emperor Xuanzong said to Zhang Shuo: "In the past, I sent envoys to inspect the good and evil of local officials in various provinces several times, but this time, I was able to visit various states in person due to the ceremony of conferring titles. I found that the envoys had failed me in many places.
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