About contact lenses

 I'm going to talk about contact lenses.
 There are three main points in which contact lenses are sperior to glasses. First , contact lenses can correct eyesight effectively because there is no distance between eyes and lenses. Second, when you play sports, contact lenses don't disturb your movements. Third, contact lenses don't change your looks. When you are wearing glasses, your eyes look smaller than your actuall size.
 However, contact lenses also have bad points. Contact lenses cover cornea so eyes lack oxygen. As a result, corneal cells decrease and clearness of cornea drops. Contact lenses also have the risk of various infectious disease. Bacteria increas on contact lenses or in lens-cases and cause infectious corneal ulcer and Acanthamoeba Keratitis. These disease have a possibility causing a visual disorder. At worst, the patients go blind.
 In order to reduce these risks, you have to use contact lenses correctly. Before using lenses, you must wash your hands. Then, after using lenses, don't forget to cleanse them. It is also important to keep a lens-case clean. Moreover, you should use glasses sometimes because it is bad for your eyes to use contact lenses for many hours everyday.
 We have no spares for our own eyes. So, let's take good care of them.