Задание

Read the text and match the subheading to the paragraphs.

A tsunami is a large wave that travels at great speed towards land. They are usually caused by an undersea earthquake, but they can also happen after a large undersea landslide and an underwater volcanic eruption.

When an undersea earthquake happens, the Earth’s tectonic plates move suddenly downwards or upwards. This usually happens on a fault line and one plate slides below the neighbouring plate causing a large amount of water to be forced upwards.

This water forms a wave. Just like when you throw a pebble into a lake, the water ripples outwards. It is the same with a tsunami, but the water doesn't stop moving until it reaches the land.

As the wave moves towards the land, it increases in speed and strength. Not all tsunamis are giant waves when they hit the shore, though. Many of them come inland as a strong and fast tide. However, the impact of the water often destroys everything in its path

After the initial tsunami hits land, there are often other waves following it, that can be just as big, which slowly get smaller over time. The same as the ripples from the pebble mentioned before, but on a much larger scale.

Water is a very powerful force and can cause tremendous damage. As well as the loss of life that a tsunami can cause, it can flatten buildings and trees and destroy whole ecosystems.

Below the surface

A sudden movement

Happening one after the other

High tide

Less by degree

Deadly power