It's really just the result of the virus dividing within cells of your skin, and producing a lot of dead cells.

这便是病毒在皮肤细胞内部,分裂的结果,这个过程会产生大量的死亡细胞

耶鲁公开课 - 生物医学工程探索课程节选

They're simply working within their own very narrow ambit.

他们只是简单地在有限范围的内部工作

耶鲁公开课 - 古希腊历史简介课程节选