You must keep quite while walking. You mustn't talk in the library. You must keep the books clean during reading. You mustn't eat in the library. You must put the books back to the bookshelf after reading. You mustn't damage the books.
When you are in a library, there are several rules you need to follow. First of all, you must be quiet in the library. And then, you mustn't eat or drink inthe library. Also, you must put the boo...