Just type "Dear Dr. " and following it insert the mergefield that contains
the last name of the recipients.
Instead of using the Mailmerge wizard, I suggest that from the View menu,
you select Toolbars and then check the Mailmerge item to turn on the
Mailmerge toolbar. That toolbar gives you all of the functionality that you
need to create and execute a mailmerge.
--
Please post any further questions or followup to the newsgroups for the
benefit of others who may be interested. Unsolicited questions forwarded
directly to me will only be answered on a paid consulting basis.
Hope this helps
Doug Robbins - Word MVP