is validated by the changing composition of the nation 
(ROOT (VP (VBZ is) (VP (VBN validated) (PP (IN by) (NP (NP (DT the) (VBG changing) (NN composition)) (PP (IN of) (NP (DT the) (NN nation))))))))
(ROOT (VP (VBZ ) (VP (VBN ) (PP (IN ) (NP (NP (DT ) (VBG ) (NN )) (PP (IN ) (NP (DT ) (NN ))))))))