整数集合{                                                         …}

正数集{                                                          …}

负分数集{                                                        …}

无理数集合{                                                    …}．

①自然数集合{                                     ……}

②整数集合{                                     ……}

③非正数集合{                                     ……}

④正分数集合{                                     ……}

⑤正有理数集合{                                     ……}

⑥无理数集合{                                     ……}

-3，- ，-|-3|，π，-0.3，0， ，1.1010010001

整数：{       }
负分数：{     }
无理数：{      }