Each barb branches into barbules, which link to one another by hooks.

每根羽支分拨成小羽，小羽通过钩子相互连接。

And lots of times, there are little feather barbules in there that we can look at the microscopic characters

很多时候， 里面有小羽毛，我们可以看到微观特征。

The central part of the feather became a hardened structure called a rachis, with lots of little barbs and barbules, creating the vanes of the feather.

羽毛的中央部分变成了一种称为羽轴的硬化结构，上面有许多小倒钩和小枝，形成了羽毛的叶片。