你相信机经的作用吗?不管你信不信，我信了
如果你想了解为什么"预测"和"机经"是有用的。
首先，尝试阅读下面这段话并真正耐心读完后再看下文的说明：
Comprehension:
What is this text about?
The procedure is actually quite simple. First you arrange things into different groups. Of course, one pile may be sufficient depending on how much there is to do. If you have to go somewhere else due to lack of facilities, that is the next step; otherwise you are pretty well set. It is important not to overdo things. That is, it is better to do too few things at once than too many. In the short run this may not seem important, but complications can easily arise. A mistake can be expensive as well. At first the whole procedure will seem complicated. Soon, however, it will become just another facet of like. It is difficult to foresee any end to the necessity for this task in the immediate future, but then one never can tell. After the procedure is completed, one arranges the materials into different groups again. Then they can be put into their appropriate places. Eventually they will be used once more, and the whole cycle will then have to be repeated. However, that is part of life (Bransford & Johnson, 1973, pp. 400).
这段话在讲什么内容？这个procedure是什么，也许你读完觉得不能理解，或者毫无意义，原因在于这段文字没有上下文背景。其实这段文字讲的是laundry，现在，你知道主旨是laundry之后再次阅读这段话。
以上信息读起来的感觉就完全不同了，这些内容有了真正的含义。这段文字是叫你如何洗衣服的指导信息。事实上，现在你已经知道了文字的背景，再要求你无视背景来阅读这段话几乎是不可能实现的了。
这是图式理论的一种范例，解释我们的大脑如何对世界进行分类。从本质上来说，图式是围绕某个特定主题的心理框架，帮助我们处理和归类新信息。
比如，狗的图式信息包括它们的身体（比如四条腿、有毛发、有尾巴）、它们的行为（如吠叫、流口水、追逐猫）或者它们的品种（游戏邦注：如牧羊犬、猎犬、贵宾犬）。而且，狗图式还包括更高层次图式的特征，如属于哺乳动物（温血、脊椎动物、胎生）和适合作为宠物饲养（喜欢家庭生活、忠诚、训练有素）。所以，当遇到狗时，我们的心理图式便会调用这些信息，让我们知道这种动物会有何种行为。
This transformation is an example of schema theory, which tries to explain how our brains categorizes the world. Essentially, a schema is a mental framework centering on a specific theme, helping us process and classify new information.
当你在阅读或者听力（尤其是第二语言）时，背景信息的作用能够帮助你理解文章。
The context is much more accessible for those test-takers equipped with subject-related background knowledge.
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