( ( Ordinary matter ) ( ( consists ( of ( electrons ( surrounding ( ( ( the nucleus ) , ) ( which ( is ( composed ( of ( ( ( ( neutrons and ) protons ) , ) ( ( each ( of which ) ) ( is ( believed ( to ( contain ( three quarks ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Ordinary) (NN matter)) (VP (VBZ consists) (PP (IN of) (NP (NP (NNS electrons)) (VP (VBG surrounding) (NP (NP (DT the) (NN nucleus)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ is) (VP (VBN composed) (PP (IN of) (NP (NP (NNS neutrons) (CC and) (NNS protons)) (, ,) (SBAR (WHNP (NP (DT each)) (WHPP (IN of) (WHNP (WDT which)))) (S (VP (VBZ is) (VP (VBN believed) (S (VP (TO to) (VP (VB contain) (NP (CD three) (NNS quarks)))))))))))))))))))) (. .)))
Ordinary matter consists of electrons surrounding the nucleus, which is composed of neutrons and protons, each of which is believed to contain three quarks.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD three) (NNS quarks)) (PP (IN in) (NP (DT each) (NN proton) (CC and) (NN neutron))))) (. .)))