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Ideally, people would like to know when an earthquake is going to happen and how bad it will be. In both Japan and China, people have long believed that earthquakes can be forecast. In Japan, scientists have wired the Earth and sea to detect __1__. The Chinese have __2__ watched animals and plants for warning signs of earthquakes. For example, the Chinese have noted that before an earthquake, hens' behavior changes — they refuse to enter their cages at night. They have also noticed that snakes come out of the ground to freeze to death and that dogs bark a lot, even __3__ quiet dogs. Before the Hanshin earthquake in Japan, there were reports of large schools of fish swimming near the __4__ of the water. Certain birds, like pigeons, also seemed to be especially noisy and were reported to be flying in __5__ patterns before the earthquake. Perhaps most __6__, and most easily measured, is a chemical change in ground water before a quake. Experimental data seem to indicate that the amount of radon (Rn) in the water under the surface of the Earth waxes before an earthquake. People would also like to be able to prevent the great __7__ of property caused by earthquakes. After all, most of the people who die in earthquakes are killed by falling buildings. Therefore, building structures that can withstand the power of earthquakes is a major concern. Steel seems to be the best material, but not if it is welded to form a rigid structure. Many new structures are __8__ with a new type of steel joint, an I-joint, which appears to be the most durable type of joint. These joints of steel can move without breaking. Also, to prevent property __9__, architects now design buildings so that the building's columns and horizontal beams are of equal strength, and vertical support columns are inserted deep into solid soil. In addition, many new houses have __10__ light roofs and strong walls. Concrete pillars for highway bridges that previously only had steel rods inside are now enclosed in steel.
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