The code could mean the name of the letter, the initial letters, stationery, CARDS, place names or something else.

密码可能是所有字母的名字，最初的信件，或一个人使用的文具，名片，或其他地方。

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A capital letter is used to begin a sentence or the name of a person or place.

在句子、人名或地名的开头，要用大写字母。

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What is the first capital letter of your English name?

你英文名字的第一个大写字母是什么？

youdao

As the name of the letter implies, Sullivan's methods are technical.

FORBES: Magazine Article

Other analysts have speculated that the company could buy up production businesses, even suggesting that Apple and ITV could settle their potential tug-of-war over the three-letter name by the simple expedient of the former buying the latter.

FORBES: Apple's iTV Cannot be Called iTV

Planets orbiting stars beyond the sun are labelled merely with the name of the star and a suffix letter.

ECONOMIST: Time to start giving extrasolar planets proper names