( ( D structures ) ( ( will ( help ( scientists ( determine ( better ( ( the effects ) ( of ( ( the sun ) ( on ( the earth ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP D) (NNS structures)) (VP (MD will) (VP (VB help) (S (NP (NNS scientists)) (VP (VB determine) (S (ADJP (JJR better)) (NP (NP (DT the) (NNS effects)) (PP (IN of) (NP (NP (DT the) (NN sun)) (PP (IN on) (NP (DT the) (NN earth))))))))))) (. .)))
D structures will help scientists determine better the effects of the sun on the earth.
(ROOT (S (NP (NP (NNS Studies)) (PP (IN of) (NP (NN earthquake) (NNS waves)))) (VP (VBP have) (VP (VBN helped) (S (NP (NNS scientists)) (VP (VB determine) (NP (NP (DT the) (NN structure)) (PP (IN of) (NP (NP (NN earth) (POS 's)) (NN interior)))))))) (. .)))
Studies of earthquake waves have helped scientists determine the structure of earth's interior.