验证码英语是 "CAPTCHA"，它是由英文 "Completely Automated Public Turing test to tell Computers and Humans Apart" 的首字母缩写构成的。它是一种用于区分人类和计算机的技术，旨在防止机器人或计算机软件自动进行恶意活动，例如网络爬虫、网络欺骗或恶意注册。

例句：

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