Required word in your 1st reply to a thread FREE or PAID

[ɔɔɔɔɔɔuɥoɾ]

Hi, I would like to see if its possible for a mod that would let you have a required word(s) in a members 1st reply on a chosen board.

So if the required word was "SMF" they would have to use that word in there 1st reply to a thread, all other replies after that can be freely worded and do not require the chosen word to be used.

and more that one variation  of a word to, for example if the chosen word was "Thankyou" we would have the option to add multiple words to make up for the words variations like "thanks" "thanx" and so forth

also the ability to set this for only boards of your choice, the whole forum using this would be annoying lol...

Thanks in Advanced.