And the strangest thing was: Confuciusornis was neither an ornithurine nor an enantiornithine.

孔子鸟既不是鸟氨酸也不是对映鸟氨酸。

Some opposite birds didn't have teeth, and some early ornithurines didn't either.

一些相对的鸟类没有牙齿，一些早期的鸟类也没有。

Some opposite birds didn’t have teeth, and some early ornithurines didn’t either.

一些对立的鸟类没有牙齿， 一些早期的鸟雀类也没有。

But in ornithurines this same area became covered in keratinous beak tissue, while they kept the teeth that were farther back in their jaws.

但在鸟科动物中， 同样的区域被角质喙组织覆盖，同时它们将更靠后的牙齿保留在下巴中。