Situation: I've been sitting by this desk for a few hours but I still have finished the book I got from the bookshelf behind me.
Alternative situations: I sat down at the desk to eat my lunch and the bookshelf was to my left. I am sitting in the cubicle in the bottom left corner, another cubicle in front of me, I need a book in cubicle.
Question: How many bookshelves are to my left?