This blue chain here goes from 5' carbon all along the chain and there's a 3' carbon left open at the bottom.

这条蓝色的链,从5'碳开始一直向下延伸,以3'碳做为链的末端

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So essentially, we have two ethene or ethylene molecules here to start with where these blue are our 2 s p 2 hybrid orbitals, so you can see that for each carbon atom, one is already used up binding to another carbon atom.

本质上，我们从两个乙烯分子开始,蓝色的是2sp2杂化轨道，你可以看到，对于每一个碳原子，其中一个已经用来和另外一个碳原子成键。

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