圖書館理員既工作職責英文應該點寫丫....

我想你指的是Library Assistant (圖書館助理)而非Librarian (通常指圖書館長)
Library Assistant的duty有好幾個，怎可用一個英文字代表呢?
那我就用英文儘量簡單撮要地寫啦:

Duties of Library Assistant:

--Circulation: acting as a part in the circulation process of library materials
--Customer services: dealing with library users, satisfying their needs & questions
--Reference Desk: helping library users in searching library materials
--Paper works: paper works like filing, creating reports, etc.
--Maintenance: maintaining the library materials and also the library environment

大概咁多，希望幫到你！