Close the pipeline. Tianjin Hexi District Library closed on Monday to avoid readers' working hours. Usually, readers have leisure time to read books on Saturdays and Sundays, and most of them work or attend classes on Mondays, so the library is open on Saturdays and Sundays and closed on Mondays. In order to better serve readers, librarians are open on weekends and holidays, and they will choose to rest with readers on Mondays.