It is a nine-digit number that begins with the number 9, and the 4th and 5th digits, also known as second section (xxx-xx-xxxx), range from 70 to 88, 90 to 92 and 94 to 99.
它是一个首位为数字9的九位数，且它的第四位和第五位数字也称为第二分区（英语：second section，xxx-xx-xxxx），其范围在70到88、90到92和94到99之间。