Go to any deal that you want to Pass or put On hold. Make sure they have Contact Person listed in the Associated people.
Now select "Pass" or "On hold"
Once in Pass, amke sure you have recorded the "Pass reason". Then turn on "Send rejection notification". Then you will see the contact person and a message that can be edited. Do the needed edits. Once the message is ready, you can send it and also this edited message will be stored the next time you pass of a deal.
Hope this helped!