Most schools teach children lowercase letters first, and uppercase letters later.

大多数学校先教孩子们小写字母，后教大写字母。

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Lowercase letters in the text are left unchanged.

文本中的小写字母保持不变。

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You can also spell the strings using mixed uppercase and lowercase letters.

还可以用混合大小写字母的形式拼写字符串。

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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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