这种设计有几个原因——首先，创造这样一个20级的职业将同艺人，修士，贵族，以及学士（同学者最接近的职业）有太多的重复。

This decision was made for several reasons — primarily, to create such a Class over 20 Levels would cause too much overlap with Artisans, Godsworn, Nobles, and most of all, Maesters.

youdao

And the reason that they're the least sheilded is because they can get closest to the nucleus, so we can think of them as not getting blocked by a bunch of other electron, because there's some probability that they can actually work their way all the way in to the nucleus.

它们最不容易被屏蔽的原因,是因为他们可以更加接近原子，所以我们可以认为它们,最不容易被其它原子阻挡住，因为它们有一定的概率,离原子核非常近。

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