( ( ( Supernova/Neutron Star ) 4 ) . )
(ROOT (NP (NP (NNP Supernova/Neutron) (NNP Star)) (NP (CD 4)) (. .)))
Supernova/Neutron Star 4.
(ROOT (S (NP (NN Neutron) (NNS stars)) (VP (VBP are) (NP (NP (DT the) (NNS corpses)) (PP (IN of) (NP (ADJP (VBN left) (RP over)) (NN supernova) (NNS explosions))))) (. .)))