( Stars ( ( ( are mostly ) ( made ( of ( ( hydrogen and ) helium ) ) ) ) . ) )
(ROOT (S (NP (NNP Stars)) (VP (VBP are) (ADVP (RB mostly)) (VP (VBN made) (PP (IN of) (NP (NN hydrogen) (CC and) (NN helium))))) (. .)))
Stars are mostly made of hydrogen and helium.
(ROOT (S (NP (NNP Saturn)) (VP (VBZ is) (VP (VBN made) (ADVP (RB mostly)) (PP (IN of) (NP (NN helium) (CC and) (NN hydrogen))))) (. .)))