Earthquake

This is part of exercise from my learning book. I hope you can correct my verb.

Almost every part of the world has experienced an earthquake in recent years and almost every part of the world is going to experience earthquakes in the years to come. Since the ancient Chinese began to keep records several thousand years ago, more than a million earthquakes have occurred worldwide by some estimates. What causes earthquakes? Throughout time, different cultures developed myths to explain these violent earth movements.

From India comes the story of six strong elephants which hold up the earth on their heads. Whenever one elephant moves its head, the earth trembles.  According to a Japanese myth, a playful catfish lives in the mud under the earth. Whenever it feels like playing, it waves its fat tail around in the mud. The result? Earthquakes. 

Nowadays, although scientists have learned more about the causes of earthquakes, they still cannot prevent the terrible damage. One of the strongest quakes in the last hundred years happened in Anchorage, Alaska, on March 24, 1964, at about six o'clock in the evening. When the earthquake struck that evening, many families were sitting down to eat dinner. People in the city (find, suddenly) found themselves in the dark because most of the lights in the city went out when the earthquake occurred. Many people died instantly when tall buildings collapsed and sent tons of brick and concrete crashing into the streets. When is the next earthquake going to occur? No one really knows for sure.

Interestingly enough, throughout history animals had often helped people predict earthquakes shortly before they happen. At present, some scientists have studied catfish because catfish swim excitedly just before an earthquake.  According to some studies, snakes, monkeys, and rodents have also appeared to be sensitive to the approach of violent movement in the earth's surfaces. Some animals seem to know a great deal more than humans about when an earthquake will occur.

In recent years scientists have developed many extremely sensitive instruments. Perhaps someday the instruments could be able to give us a sufficiently early warning so that we can be waiting calmly in a safe place when the next earthquake strikes.