现在社会存在很多有关眼睛的问题，严重的甚至使人失明或丧失性命。眼睛不仅是心灵的窗户，也是人辨别真假好坏的最基本器官，因此保护自己的视力刻不容缓，要经常作眼保健操，保持良好的用眼习惯。 视力用英语表达是 vision，sight 或 eyesight，表示看的能力，它们是不可数名词，那么视力不好可以用 poor vision/sight/eyesight 来表示。类似描述视力的形容词还有 good，blurred，little，normal，failing 或 perfect 等，例如： She has very little vision in her left eye.她的左眼视力很差。She has very good sight.她的视力很好。Her eyesight is failing.她的视力日渐衰退。He suffered from poor eyesight and could no longer read properly.他视力不好，再也不能正常阅读了。那么失明用英语表达就是 lose one's vision/sight/eyesight，此时意思相当于 blind，因此我们还可以用 become/go blind 来表示失明，其中的 become 和 go 都是系动词，例如：Doctors think he will become/go blind.医生们认为他会失明。He started to become/go blind in his sixties.他六十多岁时开始失明。
Blind 不仅可以用来形容人的眼睛的失明，而且可以用来表示人对什么视而不见或未察觉的，例如：She seems to be blind to his faults.她似乎无视他的缺点。I must have been blind not to realize the danger we were in.当时我一定是眼瞎了，竟然没有意识到我们所处的危险。因此在表示某人视力不好时，还可以用习语 (as) blind as a bat，字面意思是“和蝙蝠一样瞎或视力不佳”，类似的还有 (as) blind as a beetle/mole，例如：He lost his sight in an accident and is as blind as a bat.他在一次事故中失明后瞎了。After neglecting his vision for years, my grandfather became blind as a bat, unable to even see shadows.在多年忽视视力之后，我的祖父的视力变差了，甚至看不见影子。这个习语还常用来表示对问题或不好的行为视而不见，可以意为“置若罔闻，视而不见”等，相当于 turn a blind eye (to sth)，例如：1. (as) blind as a bat:Maria is so in love, she is as blind as a bat when it comes to Mark’s rude behavior.玛丽亚太爱马克了，她对马克的粗鲁行为置若罔闻。Jenny’s husband is as blind as a bat even when he knows that she is having an extramarital affair.珍妮的丈夫即使知道她有婚外情，也视而不见。Connie is blind as a bat when it comes to her daughter's disgraceful behavior.康妮对她女儿的可耻行为视而不见。2. turn a blind eye (to sth): Can't you just turn a blind eye to this little incident, instead of telling Mom and Dad?你就不能对这件小事视而不见，而不告诉爸爸妈妈吗？The usher turned a blind eye to the little boy who sneaked into the theater.门卫对那个溜进剧院的小男孩视而不见。其实表示视力不好的最通俗的表达方式是 be not able to see well，此时这里只能用 see，而不能用 look 或 watch，因此 see 在这里表示用眼睛看的本能，例如：He is not able to see well in low light.他在微光下视力不好。
