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                                                                                                     塞下曲
                                                                                                      李白
                                                               五月天山雪，无花只有寒。笛中闻折柳，春色未曾看。
                                                               晓战随金鼓，宵眠抱玉鞍。愿将腰下剑，直为斩楼兰^①。
                                                                   【注】①楼兰：这里泛指侵扰西北的敌人。