( ( ( Another event ) ( that ( generates ( ( a ( large amount ) ) ( of ( gravitational radiation ) ) ) ) ) ) ( ( is ( ( ( the collapse ) ( of ( ( a ( massive star ) ) ( in ( a ( supernova explosion ) ) ) ) ) ) ( to ( form ( a ( neutron star ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT Another) (NN event)) (SBAR (WHNP (WDT that)) (S (VP (VBZ generates) (NP (NP (DT a) (JJ large) (NN amount)) (PP (IN of) (NP (JJ gravitational) (NN radiation)))))))) (VP (VBZ is) (NP (NP (DT the) (NN collapse)) (PP (IN of) (NP (NP (DT a) (JJ massive) (NN star)) (PP (IN in) (NP (DT a) (NN supernova) (NN explosion))))) (S (VP (TO to) (VP (VB form) (NP (DT a) (NN neutron) (NN star))))))) (. .)))
Another event that generates a large amount of gravitational radiation is the collapse of a massive star in a supernova explosion to form a neutron star.
(ROOT (S (NP (NP (DT The) (NN core)) (PP (IN of) (NP (DT a) (NN star)))) (VP (VBZ collapses) (PP (IN during) (NP (DT a) (NN supernova))) (, ,) (S (VP (VBG forming) (NP (DT a) (NN neutron) (NN star))))) (. .)))