Loading html from file into several text fields

I’m making a four column layout with four dynamic text fields and text that loads from a html file. The structure of the site and which html file is to be loaded on which page is specified in xml, but the actual content on each page needs to be editable in separate html files (different people will do the editing, and I don’t want them to go around messing with the structure).

The problem is that I need the four columns of text to be loaded from a single html file. I was thinking that I could make four paragraphs <p>paragraph1</p><p>paragraph2</p> etc., one for each column, but how do I load them each into a separate dynamic text field?

It would be great if someone could give me some pointers on how you could do that.