On Theoretical Foundations of CALL: Constructivism and Input-Output Hypothesis

This paper intends to discuss deeply about the theoretical foundation of CALL(Computer Assisted Language Learning)---Constructivism. Moreover, this review is ready to offer a new theoretical resource, which is often ignored by previous scholars. The author calls it SLA theoretical foundation of CALL--- a combination of Krashen's Comprehensible-Input Hypothesis and Swain's Comprehensible-Output Hypothesis'.