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

VOA: standard.2010.03.03

I would guess that probably 30% to 50% of you do this everyday, you put a piece of plastic, a synthetic piece of plastic into your eye to improve your vision.

我猜你们有百分之三十到百分之五十的人,每天会做这样的事,将一小片塑料,合成塑料放到眼睛里,来提高自己的视力

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