The most popular form of shadow theater is known as Wayang Siam.
( ( ( The ( ( most popular ) form ) ) ( of ( shadow theater ) ) ) ( ( is ( known ( as ( Wayang Siam ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (ADJP (RBS most) (JJ popular)) (NN form)) (PP (IN of) (NP (NN shadow) (NN theater)))) (VP (VBZ is) (VP (VBN known) (PP (IN as) (NP (NNP Wayang) (NNP Siam))))) (. .)))
Wayang Siam is the most popular form of shadow theater. 
( ( Wayang Siam ) ( ( is ( ( the ( ( most popular ) form ) ) ( of ( shadow theater ) ) ) ) . ) )
(ROOT (S (NP (NNP Wayang) (NNP Siam)) (VP (VBZ is) (NP (NP (DT the) (ADJP (RBS most) (JJ popular)) (NN form)) (PP (IN of) (NP (NN shadow) (NN theater))))) (. .)))