23 - She was also interested in codes and sent me emails with hidden messages.

23 -她也对密码感兴趣，给我发有隐藏信息的电子邮件。

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In antiquity, many of his followers said the books contained hidden layers of meaning and secret codes but this was rejected by modern scholars.

古时候，他的许多追随者都说书里隐藏有另一层意义和暗号，但这种说法遭到现代学者的拒绝。

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Developer shall not include any hidden text or codes in the development of the Web Site except as specifically requested by the Customer.

除非客户具体要求，否则开发方在开发网站时不得采用任何隐藏文本或代码。

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Cheat codes can be hidden in a game for players to find and then share with others.

FORBES: Magazine Article

The codes will be hidden inside the wrappers of any one of ten of Cadbury's leading chocolate bars including Crunchie, Time Out, Dairy Milk, Caramel, Boost, Wispa, Giant Buttons, Whole Nut, Fruit and Nut and Double Decker.

BBC: Eat yourself a win

Hidden within the video are secret Elvish codes.

FORBES: Riddles in the Air: Guess What AirNZ Has in Its Pockets in Hobbit-themed Promotion