阅读古诗，回答相关问题。
                                                                                                                            酬乐天扬州初逢席上见赠　　
                                                                                                                                           刘禹锡
                                                                                                                    巴山楚水凄凉地，二十三年弃置身。
                                                                                                                    怀旧空吟闻笛赋，到乡翻似烂柯人。
                                                                                                                    沉舟侧畔千帆过，病树前头万木春。
                                                                                                                    今日听君歌一曲，暂凭杯酒长精神。