put all the sub-elements for a particular element next to the element on one line

If I have a table structured in the following way:

TableA

ColumnA | ColumnB

  Cat            Ferrari
  Cat            Holden
  Cat            Ford
  Cat            Toyota

What Oracle computer code SQL or PL/SQL would twist the data so it would

display in the following way:

Cat Ferrari Holden Ford Toyota

Essentially what I am trying to do is to put all the sub-elements for a particular element next to the element on one line by extending the following code:

select ColumnA, ColumnB from TableA where ColumnA = 'Cat'; Received on Tue Dec 07 1999 - 19:19:08 CST