Classics, modern fiction, non-fiction and more. Written for secondary and adult students the Oxford Bookworms Library has seven reading levels from A1-C1 of the CEFR. Right now, all over the world, people are using energy. As we drive our cars, work on our computers, or even cook food on a wood fire, we probably do not stop to think about where the energy comes from. But when the gas is gone and there is no more coal - what then? Scientists are finding new answers all the time. Get ready for the children whose running feet make the energy to bring water to their village.