We are aware that at the end of the central hole in this outer ear there is something called the middle ear, with an eardrum and a few little bones.

 
  • 我们知道,在外耳中孔的底部有东西称为中耳,它由一个耳鼓和一些小骨骼构成。
今日热词
目录 附录 查词历史