painted on their largest-ever historical canvas 
(ROOT (S (VP (VBN painted) (PP (IN on) (NP (PRP$ their) (ADJP (JJS largest) (HYPH -) (RB ever)) (JJ historical) (NN canvas))))))
(ROOT (S (VP (VBN ) (PP (IN ) (NP (PRP$ ) (ADJP (JJS ) (HYPH ) (RB )) (JJ ) (NN ))))))