As an example, look at a service that accepts a text message consisting of a three-digit U.S. area code and returns information about that area code.

作为例子，看一下这样一个服务，它接收包含一个3位数美国区号的文本消息并返回关于该区号的信息。

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ACCOUNT T NUMBER: 1332211185When he had typed the last digit, the screen refreshed again. A message in several languagesappeared. English was on top.

账号：1332211185最后一个数字输入完毕后，屏幕又刷新了，出现了用几种不同的语言写成的信息。最上面的一段是英语。

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Here, along with your username and password, you can set your Google account to ask you for a six-digit code that Google will send via text message to your phone.

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The "two-factor" verification system, which will be optional, asks users to register a phone number, e-mail account and six-digit code that would have to be entered, via text message, each time they log in to the site.

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