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                                                                                                夜上受降城①闻笛   李益
                                                                                         回乐烽前沙似雪，受降城外月如霜，
                                                                                         不知何处吹芦管，一夜征人尽望乡。
降城：贞观二十年，唐太宗于灵州受突厥一部之降，故灵州也称受降城。