A great deal of research on second language (L2) input has provided useful linguistic evidence for the development of generalizations about and hypotheses on the usage-based nature of L2 knowledge. However, despite the fact that classrooms are one of the most ubiquitous sites of L2 learning, we still know very little about the linguistic quality…

This article shows that first language (L1) transfer may not be effectively maintained in the interlanguage due to confounding factors in the second language (L2). When two factors, "A" and "B," are correlated in the L2, second language learners may only acquire "B," even if "A" is present in the L1.…