It can be done in some cases, but the devil is in the details.
If you want this for something that will be printed/previewed/PDF'd, You can set the fields to be several rows of text tall and set them, on the Inspector's position tab, to slide up and resize the enclosing part.
If you want this in browse mode, this is more problematic. If each row of text is a record in a related table you may be able to get this result with a calculation field such as that produced by ExecuteSQL instead of a portal.
I other cases, where each row is a record and you need to be able to edit the data, it's not really possible.