The words inside of this word are " pneumono, " which has to do with your lung; " ultra, " which means very – " ultramicroscopic" means very small, something you could only see with a microscope.
这个词里面的词是“pneumono” ,与你的肺有关;“ultra” 意思是非常——“ultramicroscopic” 意思是非常小,只有用显微镜才能看到的东西。