( ( ( ( ( ( Supernova remnants ) ( leave ( behind ( ( ( neutron stars ) or ) ( black holes ) ) ) ) ) , ) so ) ( SGRs ( must ( be ( related ( to ( ( ( neutron stars ) or ) ( black holes ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NNP Supernova) (NNS remnants)) (VP (VBP leave) (PP (IN behind) (NP (NP (NN neutron) (NNS stars)) (CC or) (NP (JJ black) (NNS holes)))))) (, ,) (IN so) (S (NP (NNP SGRs)) (VP (MD must) (VP (VB be) (VP (VBN related) (PP (TO to) (NP (NP (NN neutron) (NNS stars)) (CC or) (NP (JJ black) (NNS holes)))))))) (. .)))
Supernova remnants leave behind neutron stars or black holes, so SGRs must be related to neutron stars or black holes.
(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))))) (. .)))