wit: 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/wit - from package: wit

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

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