Install klettres-data by entering the following commands in the terminal:
sudo apt update sudo apt install klettres-data
Description:
data files for KLettres foreign alphabet tutor
This package contains architecture-independent data files for KLettres, the foreign alphabet tutor for KDE. . This package is part of the KDE education module.
Homepage: http://edu.kde.org/
Version: 4:17.12.3-0ubuntu1
Section: universe/kde