sentence2_structure: Studies of earthquake waves<>have helped<>scientists determine the structure of earth's interior$$$scientists<>determine<>the structure of earth's interior
sentence1: Seismologists study the location and force of earthquakes and trace the behavior of earthquake waves to interpret the structure of the Earth.
sentence2: Studies of earthquake waves have helped scientists determine the structure of earth's interior.
question: Studies of earthquake waves have helped scientists determine the