Install kde-l10n-zhcn by entering the following commands in the terminal:
sudo apt update sudo apt install kde-l10n-zhcn
Description:
zh_CN (zhcn) localization for KDE
This package contains the translation files for all KDE core applications for the language "zh_CN".
Homepage: http://l10n.kde.org/team-infos.php?teamcode=zh_CN
Version: 4:17.08.3-0ubuntu4
Section: universe/kde