Esta página está en blanco intencionadamente.
The exercises are not created yet. If you would like to get involve with their creation, be a contributor.
Open TextBooks are collaborative projects, with people from all over the world bringing their skills and interests to join in the compilation and dissemination of knowledge to everyone and everywhere.
Become an Ambassador and write your textbooks.
Become a Books4Languages Online tutor & teacher.
More information here about how to be a tutor.