As it grows,a cauliflower plant will start to form a head.

VOA: special.2010.03.09

Different kinds of polarity form, there's a head, and there's a tail, there's a back, there's a front, there's a left side and there's a right side.

不同的极性开始形成,有头端,也有尾端,有后面,也有前面,有左侧,也有右侧

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These 2 are going to come together like this, and the first bond that we're going to form is going to be a sigma bond, right, so we see that here. If we're looking head on, we see they form a sigma bond.

它们两个会靠近到一起，首先会形成的是,一个sigma键，对吧，我们在这里可以看出来，我们看到它们形成一个sigma键。

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