The code is the first four digits of every cell phone number. No matter where you are, you cannot call a cell phone number without this code.

这个代码就是手机号的前四位，不管从哪个地方打电话，都不能少了这4位。

youdao

If a match is made, the first three digits are captured in the first set of parentheses, the next three digits in the second set; and the final four digits in the remaining operator.

如果找到匹配，则把前三个数字捕捉到第一组括号中，把接下来的三个数字捕捉到第二组括号中；并且把最后四个数字捕捉到剩余操作符中。

youdao

Seven lowercase and alphanumeric characters, first three characters being alphabetic and the last four characters being digits.

七个小写字母和字母数字字符，前三个字符为字母，而后四个字符为数字。

youdao

Kinsley said the base was requesting each individual's full name, including middle initial, driver's license, and full social security number, in order for background checks to be performed before the race, compared with the standard procedure of first and last name and last four digits of one's social.

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This was lower than many had expected and the first time in four years a quarterly growth figure was in single digits.

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