Then, you've got to say, "What do I have to know about this object at the initial time?

然后,也许你会问,我需要知道物体初始状态的哪些信息呢

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And it's pretty expensive to do so because I think they know you need to do it.

这样做很贵，因为我想他们知道你需要这么做。

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So what I decided is that you need to know the whole book in the sense that you need to know all of the key terms and key points.

所以我决定了,我把掌握整本书的要求改为,你需要知道所有的关键词和关键点

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