例句:It forces them to abandon their mental model of a single unified document and forces them to think in terms of the implementation model—that there is one document embedded within another, and each has a separate editor with a separate Undo buffer. 用户无法理解这一点,这让用户不得不放弃心理模型中认为的这是一体的一个文档。 用户不得不按照实现模型来思考——实际上是两个文档,一个嵌套着另一个,每个文档都有单独的编辑器和撤销缓冲区。