I believe that a good libary benefits all of us.It is a place where we can improve our study and enhance our knowlages from reading various books.In order to keep the library in good order,we must obe...Key words!!!!We must be quiet. We mustn't make noise.We must return books . We mustn't take book. We mustn't drop litters。We must obey rules. We mustn't have smoking.We mustn't have eating，We mustn't drinking in the libary.