dynamic string in actionscript

My syntax is all messed up and I'm not very good with actionscript. If anyone could take a look at this it would be greatly appreciated:

//Location of CSS and text files to load.
var txt_url:String = "terms" + _root.id + ".html");
var txt_url:String = "terms" + _root.id + ".css");

So I have a FlashVar="id=1"

I need the string to end up being:

var txt_url:String = "page1.html");
var txt_url:String = "page1.css");

Thanks for looking!