Read the following words and phrases and their definitions.
- to be beyond help - to be at a point where nothing can be done to make things better
- bedrock - the solid rock that lies under the surface of the ground
- worn away by erosion - gradually destroyed by natural forces
- limestone - a whitish-coloured rock
- susceptible - easily affected, influenced or harmed by something
- cracks and crevices - a narrow openings in a hard surface, especially in rock
- pumice - a gray stone that comes from volcanoes and is full of small holes
- to erode - to be gradually destroyed by natural forces such as water, wind or ice
- sewer pipes - pipes that are usually underground and that are used to carry off water and such
- in the blink of an eye - very quickly
- to detect - to discover or notice
- How do sinkholes form? Explain in your own words.
- Why do sinkholes often form in places that are built mostly on limestone?
- Do sinkholes always form as a result of natural causes? Explain your answer.
- In which country can the most famous sinkhole be found?
- What can people do to avoid sinkholes?
- What crazy natural disaster are you afraid of?
