( ( A star ) ( ( ( shines ( by ( ( nuclear fusion ) ( between particles ) ) ) ) ( at ( ( the center ) ( of ( the star ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN star)) (VP (VBZ shines) (PP (IN by) (NP (NP (JJ nuclear) (NN fusion)) (PP (IN between) (NP (NNS particles))))) (PP (IN at) (NP (NP (DT the) (NN center)) (PP (IN of) (NP (DT the) (NN star)))))) (. .)))
A star shines by nuclear fusion between particles at the center of the star.
(ROOT (S (NP (NP (JJ Nuclear) (NN fusion)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ results) (PP (RB because) (IN of) (NP (NP (JJ great) (NN pressure)) (PP (IN at) (NP (NP (DT the) (NN center)) (PP (IN of) (NP (DT a) (NN star)))))))))) (, ,)) (VP (VBZ causes) (S (NP (NNS stars)) (VP (TO to) (VP (VB shine))))) (. .)))