I'm a librarian.
If you can’t find a book in the library, just ask the librarian.
The librarian showed us that we must be quiet.
That librarian had to read lots of books.
A librarian at my high school is very nice
She is a librarian, not a secretary.
The librarian returned with the book I wanted.
I told the librarian that I needed the book for a report due on Friday; so she said she would call it in.