( ( ( ( plate boundaries ) , ) ( ( ( volcanoes , ) and ) earthquakes ) ) . )
(ROOT (NP (NP (NN plate) (NNS boundaries)) (, ,) (NP (NP (NNS volcanoes)) (, ,) (CC and) (NP (NNS earthquakes))) (. .)))
plate boundaries, volcanoes, and earthquakes.
(ROOT (S (PP (IN At) (NP (DT a) (JJ convergent) (NN plate) (NN boundary))) (, ,) (SBAR (WHADVP (WRB when)) (S (NP (CD one) (NN plate)) (VP (VBZ is) (ADJP (JJ oceanic))))) (, ,) (NP (EX there)) (VP (VBP are) (NP (JJ large) (NNS volcanoes))) (. .)))