( ( Simply put ) ( , ( ( ( the ( ( increase or ) decrease ) ) ( of ( pressure ( around ( a gas ) ) ) ) ) ( ( will ( ( cause ( ( the volume ) ( of ( ( the gas ) ( to ( ( either decrease ) ( of increase ) ) ) ) ) ) ) respectively ) ) . ) ) ) )
(ROOT (S (S (VP (ADVP (RB Simply)) (VBN put))) (, ,) (NP (NP (DT the) (NN increase) (CC or) (NN decrease)) (PP (IN of) (NP (NP (NN pressure)) (PP (IN around) (NP (DT a) (NN gas)))))) (VP (MD will) (VP (VB cause) (NP (NP (DT the) (NN volume)) (PP (IN of) (NP (NP (DT the) (NN gas)) (PP (TO to) (NP (NP (DT either) (NN decrease)) (PP (IN of) (NP (NN increase)))))))) (ADVP (RB respectively)))) (. .)))
Simply put, the increase or decrease of pressure around a gas will cause the volume of the gas to either decrease of increase respectively.
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NN gas) (NNS particles)) (VP (VB heat) (PRT (RP up))))) (, ,) (NP (NN pressure)) (VP (VBP increase)) (. .)))