It does this by looking at so-called fuse bits, configuration bits that you can only write once and then afterwards read.

它通过查看所谓的熔丝位来做到这一，位只能写入一次，然后再读取。

Once I have two electrons in this 1s orbital -- so let's say the electron configuration of helium is 1s2 -- the third electron I can't put there anymore, because there's only room for two electrons.

一旦我在这 1s 上有两电子——假设氦的电子是 1s2——第三电子我不能再放在那里了，因为只有两电子的空间。