Creating letters with variable fields

I'm trying to create a standard business letter with fields for dates and company names within the body of the text. Is there a way in Adobe Acrobat or LiveCycle Designer to add a field that will allow the surrounding text of the paragraph to expand or contract depending on the size of the field?

I have Word 2007, Adobe Acrobat Pro 9.0, LiveCycle Designer ES 8.2 and Windows XP.

Thanks much!