Penguin Readers is a series of graded readers for English as a foreign language. Featuring carefully adapted texts, new illustrations, and language learning exercises, the paperback edition also includes instructions for accessing online support materials. These titles include popular classics, captivating contemporary fiction, and thought-provoking nonfiction, introducing language learners to bestselling authors and engaging content. The eight levels of Penguin Readers follow the Common European Framework of Reference for Languages (CEFR). Exercises at the back of each Reader help students practice grammar, vocabulary, and essential exam skills. Questions before, during, and after reading test text comprehension and develop vocabulary. Visit the Penguin Readers website. Exclusively with the paperback edition, readers can unlock online resources, including a digital book, an audio edition, lesson plans, and answers. In 1897, people discovered gold in the Klondike, Canada. Thousands of people traveled there to find more gold. They needed large, strong dogs to work for them. This is the story of one of those dogs, Buck. A man takes him from his family in California, and Buck is forced to pull a sled in Canada. Will he survive?