( ( ( ( Jupiter 's ) composition ) ( -LRB- ( ( mostly ( ( hydrogen and ) helium ) ) -RRB- ) ) ) ( ( makes ( it ( seem ( like ( a ( small star ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NP (NNP Jupiter) (POS 's)) (NN composition)) (PRN (-LRB- -LRB-) (NP (RB mostly) (NN hydrogen) (CC and) (NNS helium)) (-RRB- -RRB-))) (VP (VBZ makes) (SBAR (S (NP (PRP it)) (VP (VBP seem) (PP (IN like) (NP (DT a) (JJ small) (NN star))))))) (. .)))
Jupiter's composition (mostly hydrogen and helium) makes it seem like a small star.
(ROOT (S (NP (NNP Saturn)) (VP (VBZ is) (VP (VBN made) (ADVP (RB mostly)) (PP (IN of) (NP (NN helium) (CC and) (NN hydrogen))))) (. .)))