Awash in worldwide accounts of dying languages, author Leanne Hinton and a group of dedicated language activists are doing something about it: they have created a master-apprentice language program, a one-on-one approach that has been remarkably successful in ensuring that new speakers will take the place of those, often elderly, who are fluent in endangered languages. How to Keep Your Language Alive is a manual for students of all languages, from Yurok to Yiddish, Washoe to Welsh, complete with exercises that can -- and should -- be done in the most ordinary of settings, written with great simplicity and directness by a member of the linguistics faculty at the University of California, Berkeley.