( ( What ( ( this means ) ( is ( ( that ( pressure ( is ( ( the amount ) ( of force ) ) ) ) ) ( , ( or ( ( push or ) pull ) ) ) ) ) ) ) ( , ( ( exerted ( by ( ( a material ) ( on ( ( a ( given area ) ) ( of ( another material ) ) ) ) ) ) ) . ) ) )
(ROOT (S (SBAR (WHNP (WP What)) (S (NP (DT this) (NNS means)) (VP (VBZ is) (UCP (SBAR (IN that) (S (NP (NN pressure)) (VP (VBZ is) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NN force))))))) (, ,) (CC or) (S (VP (VB push) (CC or) (VB pull))))))) (, ,) (VP (VBN exerted) (PP (IN by) (NP (NP (DT a) (NN material)) (PP (IN on) (NP (NP (DT a) (VBN given) (NN area)) (PP (IN of) (NP (DT another) (NN material)))))))) (. .)))
What this means is that pressure is the amount of force, or push or pull, exerted by a material on a given area of another material.
(ROOT (S (NP (NN Pressure)) (VP (VBZ is) (VP (VBN defined) (PP (IN in) (NP (NN physics))) (PP (IN as) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NP (NN force)) (VP (VBG pushing) (PP (IN against) (NP (DT a) (VBN given) (NN area)))))))))) (. .)))