So, we see is when we use the octet rule to look at fluorine molecule, we're combining two fluorine atoms, and what we end up with is an f f molecule where they're sharing two electrons, so making that covalent bond.

那么，我们看到把八隅体规则用到氟分子上,就是把两个氟原子组合起来，最终得到的氟分子中两个原子,共用一对电子，这就构成了共价键。

麻省理工公开课 - 化学原理课程节选

Okay, so the rule for adding the two vectors is, you draw the first one and at the end of that first one, you begin the second one.

矢量的加法法则就是,先画出第一个矢量,然后在它的终点,再画第二个矢量

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