At 5:13 on the morning of April 18th 1906, the city of San Francisco was shaken by a terrible earthquake. A great part of the city was destroyed and a large number of buildings were burnt. The number of people who lost homes reached as many as 250, 000. About 700 people died in the earthquake and the fires.
Another earthquake shook San Francisco on October 17th, 1989. It was America’s second strongest earthquake and about 100 people were killed. It happened in the evening as people were travelling home. A wide and busy road which was built like a bridge over another road fell onto the one below. Many people were killed in their cars, but a few lucky ones were not hurt.
Luckily the 1989 earthquake did not happen in the centre of town but about 50 kilometres away. In one part of the town a great many buildings were destroyed. These buildings were over 50 years old, so they were not strong enough. There were a lot of fires all over the city. The electricity was cut off for several days too.
Why do earthquakes happen? Scientists explain that the outside of the earth is made of a number of different plates. At San Francisco the Pacific plate which is moving towards the northwest meets the North American plate. The Pacific plate is moving very slowly—at 5.3 centimetres a year. Sometimes these two plates stop and do not move for years. Then suddenly, they jump and an earthquake is felt. As a result of the movement of these plates, west America near the sea has always been a bad place for earthquakes. When the 1906 earthquake happened, the Pacific plate jumped 5-6 metres to the north.
Scientists are afraid that one day an even bigger earthquake will hit the area around San Francisco. They call it “The Big One”. However, people today are still building more houses. The population in and around San Francisco is now ten times more than it was in 1906. This means that if there is another big earthquake, a great many houses and buildings will be destroyed.
【小题1】Fewer people were killed in the 1989 San Francisco earthquake because the earthquake happened_______.| A．in the centre of the city | B．in the daytime |
| C．outside the city | D．in the evening |
| A．The 1906 earthquake. | B．The 1976 earthquake. |
| C．The 1989 earthquake. | D．Both A and C. |
| A．Because the surface of the earth is too thin. |
| B．Because some plates of the earth move suddenly. |
| C．Because the houses built on the earth are not strong. |
| D．Because the plates are moving slowly. |
| A．We should learn how to predict earthquakes and stop them. |
| B．We should stop building new houses. |
| C．We should build strong buildings in the right places. |
| D．We should try our best to stop earthquakes. |
| A．Bridge. | B．Road. |
| C．Car. | D．Street. |
