( Earthquakes ( usually ( ( occur ( where ( ( two plates ) ( are ( ( ( running ( into ( each other ) ) ) or ) ( sliding ( past ( each other ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (NNS Earthquakes)) (ADVP (RB usually)) (VP (VBP occur) (SBAR (WHADVP (WRB where)) (S (NP (CD two) (NNS plates)) (VP (VBP are) (VP (VP (VBG running) (PP (IN into) (NP (DT each) (JJ other)))) (CC or) (VP (VBG sliding) (PP (IN past) (NP (DT each) (JJ other))))))))) (. .)))
Earthquakes usually occur where two plates are running into each other or sliding past each other.
(ROOT (S (NP (NP (CD Two) (NNS plates)) (VP (VBG sliding))) (VP (MD can) (VP (VB increase) (NP (NP (DT the) (NN occurance)) (PP (IN of) (NP (NNS earthquakes)))))) (. .)))