( ( ( Almost ( the ( entire mass ) ) ) ( of ( the atom ) ) ) ( ( is ( concentrated ( in ( ( ( the nucleus ) , ) ( which ( contains ( ( ( ( the protons ) ( -LRB- ( ( positive charges ) -RRB- ) ) ) and ) ( neutrons ( -LRB- ( ( electrically ( neutral particles ) ) -RRB- ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (RB Almost) (DT the) (JJ entire) (NN mass)) (PP (IN of) (NP (DT the) (NN atom)))) (VP (VBZ is) (VP (VBN concentrated) (PP (IN in) (NP (NP (DT the) (NN nucleus)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ contains) (NP (NP (NP (DT the) (NNS protons)) (PRN (-LRB- -LRB-) (NP (JJ positive) (NNS charges)) (-RRB- -RRB-))) (CC and) (NP (NP (NNS neutrons)) (PRN (-LRB- -LRB-) (NP (JJ electrically) (JJ neutral) (NNS particles)) (-RRB- -RRB-))))))))))) (. .)))
Almost the entire mass of the atom is concentrated in the nucleus, which contains the protons (positive charges) and neutrons (electrically neutral particles).
(ROOT (S (NP (NNS Neutrons)) (VP (VBP are) (ADVP (RB electrically)) (ADJP (JJ neutral))) (. .)))