pushed to their most virtuous limits 
(ROOT (S (VP (VBN pushed) (PP (IN to) (NP (PRP$ their) (ADJP (RBS most) (JJ virtuous)) (NNS limits))))))
(ROOT (S (VP (VBN ) (PP (IN ) (NP (PRP$ ) (ADJP (RBS ) (JJ )) (NNS ))))))