a formula comedy redeemed by its stars , 
(ROOT (NP (NP (DT a) (NN formula) (NN comedy)) (VP (VBN redeemed) (PP (IN by) (NP (PRP$ its) (NNS stars)))) (, ,)))
(ROOT (NP (NP (DT ) (NN ) (NN )) (VP (VBN ) (PP (IN ) (NP (PRP$ ) (NNS )))) (, )))