( But ( ( the neutron ) ( ( is ( ( a ( subatomic particle ) ) ( which ( has ( ( ( more ( than an ) ) ( entire ( atom inside ) ) ) ( of it ) ) ) ) ) ) . ) ) )
(ROOT (S (CC But) (NP (DT the) (NN neutron)) (VP (VBZ is) (NP (NP (DT a) (JJ subatomic) (NN particle)) (SBAR (WHNP (WDT which)) (S (VP (VBZ has) (NP (NP (QP (JJR more) (IN than) (DT an)) (JJ entire) (NN atom) (NN inside)) (PP (IN of) (NP (PRP it))))))))) (. .)))
But the neutron is a subatomic particle which has more than an entire atom inside of it.
(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))))))) (. .)))