大部分搜索引擎使用一种倒排索引——不是针对每个单一的单词，为每个单一的网页及其上面的所有单词都编排一个目录，而是为每个单词出现的位置编排一个目录。

Most search engines use an inverted index — rather than compiling a list of every single Web page and all its words, for every single word, they compile a list of the places where it appears.

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所有现有的UDDI搜索引擎只支持单一的UDDI注册中心。

All existing UDDI search engines only support a single UDDI registry.

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但是对于单一导向的服务或搜索引擎中的相当多的网页是没有被组织和作了索引的。

But there are too many Web pages for any single directory service or search engine to organize and index.

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