on join:
   set join message to "&b&l[&c&l看守&b&l]&6&l新しい囚人%player%がきたぞ〜"

on quit:
   set quit message to "&b&l[&c&l看守&b&l]&6&lまた来てね%player%"

command /announce [<text>]:
    permission: skript.admin
    trigger:
        if arg-1 is set:
            broadcast "&b&l[&c&l看守&b&l]&6&l %arg-1%"
        if arg-1 is not set:
            message "&cこのコマンドの使い方がちがいます"