A Review of Krashen’s Input Theory

Abstract

Stephen Krashen is a famous American language educator. Krashen’s achievement in the area of second language acquisition (SLA) has won him a worldwide reputation and influence. In the 1980s, Krashen first proposed five series of hypotheses, namely, the Acquisition-Learning Distinction, the Natural Order Hypothesis, the Monitor Hypothesis, the Input Hypothesis and the Affective Filter Hypothesis, which later are collectively called the “Input Theory”. For many years, this theory has been recognized as the most comprehensive and significant theory in the area of SLA, but while gaining great recognition, this theory has been accompanied by a lot of controversies since its appearance, causing a lot of research and discussion in the academic circle. By analyzing and collating domestic and foreign literature, this paper studies the five aspects of Krashen’s Input Theory in detail, expounds their respective definitions and academic evaluation, and then points out the controversy they are facing with and the suggestions for improvement. Through the author’s research, the Input Theory has altered the idea of language instruction and offered fresh suggestions for communicative language teaching. However, this theory is supposed to be applied with consideration for the unique characteristics of each user and should be defined more explicitly in order to achieve the finest outcomes and bring more developments to the field of SLA.