PSAT Writing and Language Practice Test 39: Transitions Questions
Questions 1-10 refer to the following information.
The Benefits of Earthquakes
An earthquake results from tectonic plate activity, which starts from forces within the Earth that eventually break blocks of rock in the outer layers of the Earth. The rocks then move along a fault, or crack, 1 and most of the energy that is released travels away from the fault in different types of seismic waves.
2 Because earthquakes are often called natural disasters, in and of themselves, they are part of the forces of nature that actually help to sustain life on Earth. 3 On the other hand, the carbon cycle is made possible by plate tectonics, which, together with the water cycle, keep nutrients, water, and land available for life. This process also regulates the global temperature. Tectonic activity builds mountains and forms lakes and waterfalls as well, providing an environment in which plant and animal life can flourish. 4 In addition to their contributions to Earth's habitability, earthquakes also help scientists to make discoveries. By using seismographs around the Earth to measure seismic waves, geophysicists can determine the structure of Earth's interior.
Despite these benefits, it is still common to think of the damage that earthquakes cause. 5 Unfortunately, most earthquakes have not been disastrous. There are as many as a million earthquakes per year, 6 because most occur below the oceans sometimes as deep as about 435 miles below the Earth's surface. There was also more tectonic plate activity earlier in Earth's history, which released trapped nutrients, methane, and hydrogen that provided sufficient energy for some life-forms. Providing for a greater diversity and amount of life 7 although prepared an environment that could support advanced life. Today, the amount of earthquakes is not so great as to prevent humans from living in cities.
8 Furthermore, some earthquakes are destructive. Such destruction, however, could be avoided. About ninety-five percent of earthquakes happen in the Pacific Belt and the Mediterranean Belt. Even though it is known where earthquakes are likely to happen with a strong degree of confidence, there are still large cities in these areas that people have chosen to develop. Building cities 9 to soft ground in earthquake-prone areas leads to more damage and a greater loss of life. Structures can be built that are able to withstand even the most intense earthquakes, but this has often not been done. While tectonic plate activity provides a number of benefits, moving to locations 10 when earthquakes occur without the proper structures sometimes results in disasters.