error on belongs_to method.

I followed the Ruby on Rails up and running book published by Orielly. there are three DB tables, photo, slideshow, and slide

the Slide class in slide.rb is like this: class Slide < ActiveRecord::Base   belongs_to :photo :foreign_key =>photo_id   belongs_to :slideshow :foreign_key=>slideshow_id end

I inserted the sample data into database. When I trying to run the command on page39: slide= Slide.find 1 it give me the following error: ../slide.rb:2: syntax error, unexpected ';', expecting kEND. and the same with ../slide.rb:3

can anybody help me? if you can tell me how to debug rails, that will be more better? thanks in advance.

sorry for asking a so stupid question. I found that I missed the commas.