I recommend at LEAST a mixture of Numbers, lowercase letters, and uppercase letters.

我建议至少是数字，小写字母和大写字母的混合。

youdao

A limitation of this technique is that it only calculates Numbers between 600 and 65,000 for the specified user name format of three lowercase letters followed by four digits.

该技术的一个限制是，对于三个小写字母加上四个数字的指定用户名格式，它仅计算600到65,000之间的编号。

youdao

The name of the package itself (not the filename, just the name of the package) can contain lowercase letters, Numbers, and the "-" and "+" characters.

软件包本身的名称(不是文件名，仅仅是软件包的名称)可以包含小写字母、数字以及“-”和“+”字符。

youdao

Use a strong password which includes a combination of upper and lowercase letters and numbers.

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From there, I can change my password and they recommend that I have 8-20 characters, with a mix of uppercase and lowercase letters, numbers and special characters.

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Students spend a year building fundamentals like identifying upper- and lowercase letters and their sounds, recognizing numbers from 0 to 20, and learning physical education, music and art.

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