Shoutbox

I need some help with my script.

I know the code for changing a message sent before its sent.
But how do i make it like a list? Like this,

sent---changed

hello        hi
bye         gtg

It might not be like that but i hope you know what i mean

2nd thing is how do i make a / command for my script to turn on/off like this,

/on
/off

I hope you know what i meen...

Thanks