Stephen Krashen's L2 Acquisition Theory outlines 5 main hypotheses about second language acquisition: 1) The Acquisition-Learning Hypothesis distinguishes between acquired, subconscious knowledge and learned, conscious knowledge. 2) The Natural Order Hypothesis claims grammar structures are acquired in a predictable order. 3) The Monitor Hypothesis states that acquired knowledge is primary, while learned knowledge acts as a monitor for conscious editing. 4) The Input Hypothesis argues we acquire language through comprehensible input just beyond our current level. 5) The Affective Filter Hypothesis posits factors like motivation and anxiety can raise or lower students' affective filters, impacting acquisition.

1. Stephen Krashen’s L2 Acquisition Theory Compiled by Doris Shih

9. ING (progressive) PLURAL COPULA (“to be”) AUXILIARY ARTICLE IRREGULAR PAST REGULAR PAST SINGULAR (-s) POSSESSIVE (-s) The order for L2 learners (Krashen, 1977)

13. The affective filter Language Input Affective Filter Acquired Competence Language Acquisition Device