( ( NEUTRON Subatomic ) ( ( ( particle ( with ( same mass ) ) ) ( as ( proton ( but ( no ( electric charge ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP NEUTRON) (NNP Subatomic)) (VP (VBD particle) (PP (IN with) (NP (JJ same) (NN mass))) (PP (IN as) (NP (NP (NN proton)) (PP (CC but) (NP (DT no) (JJ electric) (NN charge)))))) (. .)))
NEUTRON Subatomic particle with same mass as proton but no electric charge.
(ROOT (S (NP (NP (DT The) (NN number)) (PP (IN of) (NP (NNS neutrons)))) (VP (MD can) (VP (VB vary) (PP (IN between) (NP (NP (NNS atoms)) (PP (IN of) (NP (DT the) (JJ same) (NN element))))))) (. .)))