New data shows that those who use Duolingo — a popular language app — can learn the equivalent of four semesters of university study. The app is free for all, and parents and teachers say it is a good ...

"Hola, ajedrez" means "Hello, chess" in Spanish. You've always been able to learn Spanish on Duolingo. And you'll be able to learn and practice chess on the language learning app soon. Duolingo ...