The cataracts that afflict elderly men and women after a life of sight can be removed, but not without a brief journey into a blindness even darker than what cataracts bring.

• 看了一辈子大千世界的眼球会产生晶状体混浊，这种折磨老年人的白内障是可以手术摘除的，但重见光明前不得不经历一段全盲的过程，比白内障带来的混浊不清还要黑暗。