The system works using handwritten numbers instead of letters because although others may be able to recognize your penned words, they're not so good at distinguishing your handwritten numerals.

该系统利用的是手写数字而非字母，这是因为别人或许能认出你的手写单词，却未必能轻易地识别出你手写的数字。

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System for representing letters, numerals, and punctuation marks by a sequence of dots, dashes, and spaces.

以点、横画、间隔的安排来代表字母、数字或标点符号的系统。

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The existing system of Internet top-level domain name including the support of only 26 English letters and Arabic numerals and a hyphen 0-9, 37 characters.

现有的互联网顶级域名体系只支持包括26个英文字母、连字符和阿拉伯数字0至9在内的37个字符。

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