kwordquiz: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/kwordquiz - from package: kwordquiz

You may install the required package with command apt-get install {package}
Error in other languages:
kwordquiz: bevel nie gevind nie
kwordquiz: comandă negăsită
kwordquiz: comando não encontrado
kwordquiz: commande introuvable
kwordquiz: command not found
kwordquiz: käsku ei ole
kwordquiz: không tìm thấy lệnh
kwordquiz: komanda nerasta
kwordquiz: Kommando nicht gefunden.
kwordquiz: kommandot finns inte
kwordquiz: komut yok
kwordquiz: nie znaleziono polecenia
kwordquiz: níor aimsíodh an t-ordú
kwordquiz: no se encontró la orden
kwordquiz: no s'ha trobat l'ordre
kwordquiz: opdracht niet gevonden
kwordquiz: parancs nem található
kwordquiz: perintah tidak ditemukan
kwordquiz: príkaz nenájdený
kwordquiz: příkaz nenalezen
kwordquiz: команда не найдена
kwordquiz: командата не е открита
kwordquiz: 命令找不到
kwordquiz: コマンドが見つかりません