( ( The quarks ) ( ( ( are always ) ( ( bound together ) ( within ( ( ( larger ( observable particles ) ) , ) ( such ( as ( ( protons and ) neutrons ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNS quarks)) (VP (VBP are) (ADVP (RB always)) (VP (VBN bound) (ADVP (RB together)) (PP (IN within) (NP (NP (JJR larger) (NN observable) (NNS particles)) (, ,) (PP (JJ such) (IN as) (NP (NNS protons) (CC and) (NNS neutrons))))))) (. .)))
The quarks are always bound together within larger observable particles, such as protons and neutrons.
(ROOT (S (NP (NNS Protons) (CC and) (NNS neutrons)) (VP (VBP are) (VP (VBN made) (PP (IN of) (NP (NP (NNS quarks)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBP are) (NP (NP (JJ fundamental) (NNS particles)) (PP (IN of) (NP (NN matter))))))))))) (. .)))