What happens if you install wood floors over wavy/lumpy subfloors?

Will it even out at all or get worse? Right now I have carpeting and the rooms are all bubbled up in the middle and droop down at the walls.
If I install wood over these crappy sub floors, will be be change anything? What can I do to even them out ? Is there something relatively simple?
Thanks.
Update: The house was just built 10 months ago. It was crooked the day they finished building it. I have been complaining to the builder to fix it since day one, and the jerk keeps telling me that it will settle and even out.
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