pda: command not found

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/pda - from package: speech-tools

You may install the required package with command apt-get install {package}

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