Try some language course of the Michel Thomas series, each lesson is roughly 60 minutes and audio only, it's aimed at the development of the spoken part of the

Try some language course of the Michel Thomas series, each lesson is roughly 60 minutes and audio only, it's aimed at the development of the spoken part of the language and so there are no books exercises to do. Perfect while driving. I've listened to a few CDs of the japanese and mandarin courses, really well done.