阅读赵嘏的《长安晚秋》一诗，完成题目。
                                                                                                                                      长安晚秋

                                                                                      云物凄凉拂曙流，汉家宫阙动高秋。残星几点雁横塞，长笛一声人倚楼。
                                                                                       紫艳半开篱菊静，红衣落尽渚莲愁。鲈鱼正美不归去，空戴南冠学楚囚。
      【注】赵嘏（gǔ）：唐代诗人。云物：云雾。