No matter where you go,there are many rules in the world. Rules change bad habbies ,change our life.For example ,in our school,school ask student to wear the uniforms,because we are student from NO.3 middle school,uniforms are symbols of student.And it's necessary to clean the class everyday,because clean class bring everybody happiness,and it good for our health.But in the school,we should not be allowed to make noisy when we take class,it not noly bring everyone good ideas,but we .also can learn some knowledges,and i think it's so important too. In our school,there are a lot of rules,they teach us to be a better student,we must follow these rules.