YES_NO [
  [ yes
    yeah
    yup
    sure
    okay
    correct
    right
    ( ?( ?yes that's ) [ right correct ] )
    ( ?yes it is )
    ( you got it )
    ( yes i do )
    ( yes i would )
    ( yes it is correct )
  ] {return("yes")}
  [ no
    nope
    incorrect
    ( no way )
    ( no it isn't )
    ( ?no [ it's that's ] not [ correct right ] )
    ( ?no it isn't )
    ( ?no it is not )
    ( ?no it's not )
    ( no i don't )
    ( no i do not )
    ( no i wouldn't ) 
  ] {return("no")}
]