每年的3月份，来自全国各地的人大代表和政协委员齐聚北京，共商国家大事．这体现了北京是（    ）

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                                                                                                                     一 鹭 图
                                                                                                                     刘羽（明）
                                                                                                芳草垂杨荫碧流，雪衣公子立芳洲。
                                                                                                一生清意无人识，独向斜阳叹白头。