Studying Krashen: Benny Lewis and the 5 Theories Dr. Stephen Krashen has done so much for the teaching and learning of languages through the research and publication of his five theories of language acquisition. Studying Krashen’s 5 Theories Krashen’s theory of second language acquisition consists of five main hypotheses: the Acquisition-Learning hypothesis; the Monitor hypothesis;… Read More Studying Krashen: Benny Lewis and the 5 Theories