Complete the sentences with the words from the box.
renewable/non-renewable/abundant/alternative/polluting/exhausted/fossil/available
1-Many of the Earth's natural resources are ....., which means they are available in limited quantily and can be used up.
2-Oil is a relatively ..... but is a non-renewable resource.
3-..... fuels, including coal, oil and natural gas, are currently the world's primary energy source.
4-..... resources are those which cannot be replaced once they are used up.
5-..... energy is any energy source that can replace fossil fuel.
6-Despite being the most ..... source, coal still plays an important role in the production of electricity.
7-Solar power from the sun is ..... as we won't "use up" all the sunlight from the sun.
8-Geother mal energy is non-polluting, but it not widely ..... .