The best domain names containing your keyword, and using a hyphen "-" the keyword alone exposed to facilitate the search engine recognition.

域名中最好含有你的关键字，并且采用连字符“-”将该关键字单独突显出来以方便搜寻引擎识别。

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If you want to express the matching characters by using a range instead of the characters themselves, you can use the hyphen (-) character to separate the starting and ending characters of the range.

如果希望使用范围而不是字符本身来表示匹配字符，则可以使用连字符(-)将范围中的开始字符和结束字符分开。

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