( ( For instance ) ( , ( ( ( an atom ) ( of carbon ) ) ( ( could ( be ( ( ( ( ( ( carbon 12 ) , ) ( having ( ( ( ( six ( ( protons and ) neutrons ) ) , ) ( carbon 13 ) ) ( -LRB- ( ( ( ( six protons ) and ) ( seven neutrons ) ) -RRB- ) ) ) ) ) , ) or ) ( ( carbon 14 ) ( -LRB- ( ( ( ( six protons ) and ) ( eight neutrons ) ) -RRB- ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN For) (NP (NN instance))) (, ,) (NP (NP (DT an) (NN atom)) (PP (IN of) (NP (NN carbon)))) (VP (MD could) (VP (VB be) (NP (NP (NN carbon) (CD 12)) (, ,) (VP (VBG having) (NP (NP (CD six) (NNS protons) (CC and) (NNS neutrons)) (, ,) (NP (NN carbon) (CD 13)) (PRN (-LRB- -LRB-) (NP (NP (CD six) (NNS protons)) (CC and) (NP (CD seven) (NNS neutrons))) (-RRB- -RRB-)))) (, ,) (CC or) (NP (NP (NN carbon) (CD 14)) (PRN (-LRB- -LRB-) (NP (NP (CD six) (NNS protons)) (CC and) (NP (CD eight) (NNS neutrons))) (-RRB- -RRB-)))))) (. .)))
For instance, an atom of carbon could be carbon 12, having six protons and neutrons, carbon 13 (six protons and seven neutrons), or carbon 14 (six protons and eight neutrons).
(ROOT (S (NP (DT All) (NN carbon) (NNS atoms)) (VP (VBP have) (NP (CD six) (NNS protons))) (. .)))