Make a multiline paragraph match the lines on the form

I have a form from work that has paragraphs that must be filled out.  The current version of the form has several individual textboxes to fill the paragraph.  This is very cumbersome because if information has to be added or removed to any line except the last line, all the other lines must be manually adjusted.  I am trying to get the praragraph to flow smoothly for editing content while matching the lines on the form.

I know how to make a multiline textbox and if I use size 10 font i can make it match up pretty well, but then the font size can't be adjustable in case the user needs more space.

Any suggests?

Thanks

Gary