( ( B ( Radioactive materials ) ) ( spontaneously ( ( emit ( ( alpha ( , ( beta ( , ( gamma ( , ( or neutron ) ) ) ) ) ) ) ( particles ( from ( ( the nucleus ) ( of ( ( the ( unstable atoms ) ) ( ( making up ) ( the material ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (NNP B) (NNP Radioactive) (NNS materials)) (ADVP (RB spontaneously)) (VP (VBP emit) (NP (NP (CD alpha) (, ,) (NN beta) (, ,) (NN gamma) (, ,) (CC or) (NN neutron)) (SBAR (S (VP (VBZ particles) (PP (IN from) (NP (NP (DT the) (NN nucleus)) (PP (IN of) (NP (NP (DT the) (JJ unstable) (NNS atoms)) (VP (VBG making) (PRT (RP up)) (NP (DT the) (NN material)))))))))))) (. .)))
B Radioactive materials spontaneously emit alpha, beta, gamma, or neutron particles from the nucleus of the unstable atoms making up the material.
(ROOT (S (NP (NN Beta) (NN decay)) (VP (VBZ occurs) (SBAR (WHADVP (WRB when)) (S (NP (DT an) (JJ unstable) (NN nucleus)) (VP (VBZ emits) (NP (NP (DT a) (JJ beta) (NN particle)) (CC and) (NP (NN energy))))))) (. .)))