Hospital officials say two million people in India are blind because of problems of the cornea.

VOA: special.2009.03.30

Particularly the front of the eye, the cornea and the sheet that covers the cornea was particularly damaged.

尤其是眼睛前部，角膜和盖在角膜上面的那层薄片,严重受损。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

The cornea is the clear front part of the eye that transmits light.

VOA: special.2009.03.30

(Speaking) With LASIK,doctors use a laser to permanently change the shape of the cornea to improve vision.

VOA: standard.2010.03.03