The second thing that makes a book hard to read is abstraction.

让书难以读懂第二个原因是抽象化。

In other words, this doesn't provide evidence that these ancient hashtaggers were yet fully capable of symbolic, abstract thought.

换言之，这并不能证明这些古老标签图案创作者完全有能力进行符号化、抽象化思考。

However, the actual, physical location in computer memory is hidden and abstracted by the operating system.

然而，计算机内存际物理位置被操作系统隐藏和抽象化了。

Now, all of this is easy to salute in the abstract, especially from these rarefied heights, but it's hard to protect and practice.

现，所有这些都很容易抽象化，尤其是见高度，但却很难保持和践。

You can use Metal 2, as Jeremy just talked about—that incredibly powerful low-level engine for accessing the GPU—but you might want to use a higher-level framework because that's what your abstraction would like.

你可以使用刚才杰里米说过 Metal 2，它是一个非常强访问 GPU 底层引擎，但你可能想要使用高层框架，因为你抽象化会用到它。

By the 19th century, photography was capable of producing  nature perfectly, and there is a move in the Arts towards abstraction, and away from the idea that " Art equals Beauty" .

到了 19 世纪， 摄影已经能够完美地再现自然，艺术开始走向抽象化，不再认为“艺术等于美” 。

Transformation-Generative Grammar: It sees language as a system of innate rules. Language learning is an activity of building and testing hypotheses. But at present, the influence of such a formal and abstract grammar remains limited in the field of language education.

3.转换生成语法：它将语言视为先天规则系统。语言学习是建立和检验假设活动。但目前，这种形式化和抽象化语法语言教育领域影响仍然有限。