（A）

When we feel the ground moves suddenly, it means that an earthquake may come. Many of the earthquakes first come under the sea and then happen anywhere on the earth. Especially they often happen near the mountains and seas such as Wenchuan, Japan and Indonesia.

When an earthquake happens, it’s very easy to cause a tsunami(海啸). Houses fall down, many people are injured and even died.

Now scientists are trying their best to study earthquakes. They make maps to show the “earthquake belts(地震带)”. So the houses there must be quite strong.

Webelievethatscientistswillbeabletotelluswhenandwhereanearthquakewillhappeninthenearfuture. Also, they can tell us what to do and how to do. People can even use earthquakes to do something for us humans.