Tā bèi chēngwéi huó shūkù, yīnwèi tā dú guò tài duō shū le.
He is called a living library because he has read so many books.
Tips
usage
书库 can refer literally to a physical book storage facility, or figuratively to a very learned person (活书库, 'living library'). The digital age has extended the term to online repositories and e-book databases.
