In learning-teaching of language, what do you consider most important?

According to Vygotsky's sociocultural theory of language development, social interaction is the primary engine of language learning. Language is acquired through meaningful exchanges with more knowledgeable others, peers and the community. While cognitive development, AV material, and children's literature support learning, social interaction is the most fundamental mechanism—it provides authentic context, immediate feedback, and the social purpose for communication that drives language acquisition.