Rock climbing is a popular hobby that many people enjoy doing. You can do it indoors on special walls or outdoors on real mountains. There are many advantages of rock climbing—it is fun and it also helps people forget worries.

    The most important equipment(装备)to have is good shoes. They need to be half a size smaller than your usual size. The next thing you need is a harness(保护带).This allows you to move freely, but will hold you up if you fall. It's important to know how to use your equipment. Otherwise, it may be dangerous. If you are a beginner, it's best to have lessons. A climber with experience can help you a lot in the beginning.

    Rock climbing is very exciting for people of different ages. Climbers, however, must be careful not to pollute the environment. Sometimes rock climbers leave rubbish on the mountains where they climb. They should take it with them and throw it away. This will allow future climbers to enjoy a clean environment.

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材料二 2013年8月1日，桂林市区正阳东西巷保护修缮整治改造项目正式启动，项目总投资将近8亿元，是桂林市政府十二五规划重点项目。建成后将成为桂林市打造“国际旅游胜地”的城市地标之作。这一工程是环境综合整治、城镇风貌改造的代表性项目，有利于完善城市基础设施建设；有利于美化环境，提高居民生活质量；同时通过增加经济建设支出，刺激总需求增加，有利于促进就业，拉动经济增长。