addition to hoffman 's powerful acting clinic 
(ROOT (NP (NP (NN addition)) (PP (IN to) (NP (NP (NNP hoffman) (POS 's)) (JJ powerful) (NN acting) (NN clinic)))))
(ROOT (NP (NP (NN )) (PP (IN ) (NP (NP (NNP ) (POS )) (JJ ) (NN ) (NN )))))