An earthquake happens when two plates rub (摩擦) together. The earth plates travel in different directions and at different speeds. If one plate is slowly forced under the other, pressure builds up until the plates break apart. This process causes the ground to move. It is an earthquake. In other words, earthquakes are the shaking of the earth's surface caused by the earth's rocky outer layer (岩层) as a result of the energy stored within the earth. The strain within the rocks is suddenly released (释放)．
The damage an earthquake causes depends on where it is and when it is happening. If an unpopulated region is struck, there will be low loss of life or property. If it hits a large city, there may be many injuries and much destruction. Many of the areas at risk are largely populated now. Major earthquakes hitting those areas today could produce terrible damage.
Actually, there are several million small earthquakes every year. Large earthquakes such as the 1964 Alaskan quake that measured 9.2 on the Richter scale, caused millions of dollars in damage. In the last 500 years, millions of people have been killed by earthquakes around the world — including 240, 000 in the 1976 Tangshan earthquake in China.
A 60second or less earthquake can cause devastation (破坏) that continues for years after the first tremor (震动). In 1972, a series of severe earthquakes struck Managua, Nicaragua. Fifteen years later, the city still looked the way it had a week after the earthquake hit, because the country did not have the money necessary to rebuild it.
The shaking of the earth is sometimes not the greatest disaster. It is in the ensuing fires and floods that often the greatest damage occurs. In the 1906 earthquake, it was the fires caused after it that did the majority of the damage. An earthquake can also destroy dams high above a city or valleys, causing floods to sweep down and sweep away everything in their path.
1．Which of the following is the main idea of Paragraph 1?
A．An earthquake comes from inside the earth.
B．The earth has great energy in storage.
C．How the earth plates move.
D．How an earthquake happens.
解析：选D 段落大意题。第一段主要讲述了地震的成因。
2．How many examples are used in the passage to show the damage and destruction earthquakes cause?
A．Three. B．Four.
C．Five. D．Six.
解析：选B 细节理解题。文中提到1964年阿拉斯加地震，1976年唐山地震，1972年尼加拉瓜的马那瓜地震，以及1906年地震，共四次。
3．Which of the following is mentioned to show that an earthquake can kill too many people?
A．The 1964 Alaskan quake.
B．The 1976 Tangshan earthquake.
C．The 1972 Managua earthquake.
D．The 1906 earthquake.
解析：选B 推理判断题。由第三段最后一句可知1976年唐山大地震中大约240 000人遇难。
4．The underlined word “ensuing” in the last paragraph probably means “________”．
A．causing too much heat and great damage
B．causing many injuries and much destruction
C．happening as a result of another event
D．happening suddenly and unexpectedly
解析：选C 词义猜测题。下文提到在1906年地震中，绝大部分的损失是地震引起的火灾造成的。由此推出ensuing是指“另一件事所引起的”。
