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So, we have beryllium in the first case here, it has four electrons, that's how we know it's beryllium, boron has five electrons.
那么我们将铍作为第一个例子，它有四个电子，这也是我们为什么能知道它是铍的原因，硼有五个电子。
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$firstVoiceSent
- 来自原声例句