Simplify the following text for a Grade 10 native English-speaking person.
Original: This power , although evidently envisaged as a temporary measure ( `` during a period of ten years ... and thereafter until the Parliament otherwise provides '' ) , has been used by the Commonwealth to encourage cooperation by the States to various extents over the years .
Simplified: This power , which was only meant to be used ( `` during a period of ten years ... and thereafter until the Parliament otherwise provides '' ) , has been used by the Commonwealth to encourage cooperation by the States to various extents over the years .