Cần mọi người giúp gấp!!!Please!!!
Điền từ phù hợp vào đoạn văn:

Though many stories from around the world describe behavioral changes in various animals in the days and hours before an earthquake, research testing animals' ability to predict earthquakes has been (31) ______. Recently, however, scientists were able to document the behaviors of a group of toads before, during, and after an earthquake. Researchers were studying the breeding habits of a particular group of toads, when, suddenly, 96 percent of the males simply (32) ______ for a five-day period. A significant earthquake and several aftershocks (33) ______ on the fifth day after the departure. Six days after the last aftershock, the males returned and resumed mating, as if (34) ______ had happened. It turns out that prior to the earthquake, there had been subtle changes in the Earth's magnetic field, and an increase in the amount of radon gas in the groundwater. (35) ______, there were unusual electrical disturbances in the upper atmosphere.