as a historical study and as a tragic love story 
(ROOT (PP (PP (IN as) (NP (DT a) (JJ historical) (NN study))) (CC and) (PP (IN as) (NP (DT a) (JJ tragic) (NN love) (NN story)))))
(ROOT (PP (PP (IN ) (NP (DT ) (JJ ) (NN ))) (CC ) (PP (IN ) (NP (DT ) (JJ ) (NN ) (NN )))))