students will have to stay in classrooms all day long when they are at school.so the conditions of classrooms have played an important role in student's studies and health.

　　so how to keep classrooms clean?according to the common sense ,first of all , students on duty should insist on cleaning it every day after school.secondly,it's forbidden to spit or to litter everywhere. and it's also important to educate the students to remember that it's a bad habit to draw on the walls casually without permission.and all beyond that ,it's indispensable to strengthen the mind of environmental protection and to set up a specific system on it.

　　i think everybody likes to study in a bright , beautiful classroom instead of a dirty chaotic one .so let's let started to try our best to keep our classrooms clean!