original_query: What is the Interaction hypothesis in second-language acquisition?
query: What is the Interaction hypothesis in second-language acquisition?
answer: The Interaction hypothesis posits that face-to-face interaction and communication promote second-language acquisition.  Comprehensible input, achievable through negotiation of meaning in conversations, is crucial.  Later versions emphasize the importance of  balanced interlocutor relationships and shared communicative goals for effective learning.