( It ( ( ( ( measure ( ( the height ) ( of ( ( the ( tallest wave ) ) ( on ( the seismograph ) ) ) ) ) ) and ) ( calculates ( ( the ( ( magnitude or ) strength ) ) ( of ( the earthquake ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VP (VB measure) (NP (NP (DT the) (NN height)) (PP (IN of) (NP (NP (DT the) (JJS tallest) (NN wave)) (PP (IN on) (NP (DT the) (NN seismograph))))))) (CC and) (VP (VBZ calculates) (NP (NP (DT the) (NN magnitude) (CC or) (NN strength)) (PP (IN of) (NP (DT the) (NN earthquake)))))) (. .)))
It measure the height of the tallest wave on the seismograph and calculates the magnitude or strength of the earthquake.
(ROOT (S (NP (NP (DT The) (NN height)) (PP (IN of) (NP (DT the) (NN wave)))) (VP (VBZ is) (VP (VBN used) (S (VP (TO to) (VP (VB determine) (NP (NP (DT the) (NN magnitude)) (PP (IN of) (NP (DT an) (NN earthquake))))))))) (. .)))