First, Song is misspelled to Sone, it seems.

To answer your question, use puts song.to_s to display output.  Puts is 
technically a method of Kernel, but you can use it as just puts anywhere 
in your Ruby program.

Gets does (kind of) the opposite of puts and "gets" what a user at the 
command line typed.

Dan

Kevin wrote:
> I run one of examples of Programming Ruby, code as follows:
> ------------
> class Sone
> ...
> end
> 
> song = Sone.new(.., .., ..)
> song.inspect
> song.to_s
> -----------
> why I can't see output? where is output of inspect and to_s ?
> It outputs to somewhere else? IO object ? 
> 
> thank you in advance
> 
> 
>