图 1 中引入的一个重要组件是客户端存根（stub）。

One of the import components that's introduced in Figure 1 is the client stub.

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引入新接口：不对现有接口引入行为更改的新接口通常不需要由客户端进行彻底测试。

Introduction of a new interface: a new interface that does not introduce a change in behaviour to an existing interface typically will not merit a thorough testing by clients.

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元数据概要由 HTML 4引入，其目的是为了让作者向客户端提供一种或多种文档查看或分类的方法。

Metadata profiles were introduced in HTML 4 to allow an author to provide clients with one or more ways of categorizing or viewing a document.

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