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

让书难以读懂的第二个原因是。

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

换，并不能证明些古老的标签图案创作者完全有能力进行符号、的思考。

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

然而，计算机内存中的实际物理位置被操作系统隐藏和了。

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

现在，所有些都很容易，尤其是站在罕见的高度，但却很难保持和实践。

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，不再认为“艺术等于美” 。

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的 Metal 2，它是一个非常强的访问 GPU 的底层引擎，但你可能想要使用高层框架，因为你的会用到它。

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：它将语视为先天规则的系统。语学习是建立和检验假设的活动。但目前，种形式和的语法在语教育领域的影响仍然有限。