An item tree is a heavyweight object that takes time to build, and it is a structure you have to use an XML parser on.

一个条目树是一个重量级的对象，需要花时间去构建，并且它是一个您必须使用xml解析器才能解析的结构。

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Such modifications of the document structure during parsing can result in a smaller memory footprint for the DOM tree, and also reduce the time spent traversing a document and modifying it in memory.

这种在解析期间修改文档结构的做法可以使 DOM 树占用更少的内存，而且还可以减少在内存中遍历和修改文档时所花的时间。

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The filesystem's tree structure, tied together with.. and. Entries, is built automatically each time you create a new directory.

文件系统的树状结构在每次创建一个新目录时，自动把. .和。目录项捆在一起。

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