Câu hỏi:

Earthquakes are the deadliest of all natural disasters. Most deaths are caused by collapsing buildings or fires. Several million earthquakes occur in the world each year. However, many of these are undetected because they occur in remote areas are very weak. On average, there are eighteen major earthquakes and one great earthquake each year. The most recent major earthquake took place on the island of Haiti in the West Indies. The Hitian government reported that 230,000 people had died, 300,000 had been injured and one million became homeless. Earthquakes are most common near large cracks in the Earth’s crust, known as “faults”. They often occur in southern Europe, where two large slabs of crust are moving towards each other. 

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