It builds on Unicode [Unicode Consortium technical report and ISO standard] to define strict rules for text format as well as the Document Type Definition (DTD) validation language.

它在Unicode [unicode Consortium技术报告和ISO标准]的基础上定义了文本格式的严格规则，以及Document Type Definition(文档类型定义，DTD)验证语言。

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DTD fragments in element definitions come from the strict document type definition except for the elements related to frames.

除了和框架有关的元素外，所有的有关元素定义DTD片段都来自严格文档类型定义(DTD)。

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