Sendak's parents would sometimes talk about the dead family members, especially children, who were not lucky enough to survive like Maurice had.
VOA: special.2009.10.05
So now that we have enough practice drawing Lewis structures let's talk about actually figuring out this formal charge.
那么现在我们已经做了足够多的画路易斯结构的练习,让我们来讨论一下如何得出形式电荷。
VOA: special.2010.06.20
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