natural number 自然数 positive number 正数 negative number 负数 odd integer/number 奇数 even integer/number 偶数 Integer/whole number 整数 positive whole number 正整数 negative whole number 负整数 consecutive number 连续整数 real/rational number 实数,有理数 Irrational number 无理数 inverse /reciprocal 倒数