ListView or TreeView?

Hello!

I want to realize some sort of list that also shows up to one sublevel.
That means that I might have a Top Level Row that may contain

A | B | C | D | C

The user is able to enter each of those values.
The user is also allowed to add new rows in the top level (that have the same structure), BUT he can also add rows into the sublevel (using the same structure). Listviews look great, but I think they can't display Level structures, do they?

I mean treeViews would be great, but I don't know whether they can display different columns per row. Or maybe the is another control that combines the features ob both ListView and TreeView?

Thanks a lot!