From: Pascal on
reading the post i think it's not enough clear.

To distinguish words that I consider a good response from others, I thought:
1) identify them in a RichTextBox by clicking on each, and then apply
special format (fontsize, fonttype etc.).
2)Then using a regex that would test the format of the word (font etc.), and
change it by a particular tag :
by pattern A if regex detects that the word is written with font
Arial
or by pattern B if it is font Tahoma.

hope it's more explicit.
pascal