1. How can tides make electricity?
2. When will we perhaps have to go back to horses and carriages?
3. What did some people carry in big bags in the last war?
4. Why did they do this?
5. When does a tide turn a turbine?
6. How do waves turn turbines?
7. Why can't we cut down all our trees to make gas?
8. Which makes electricity more cheaply, coal or the water in rivers?