This article presents a review of research that has investigated ways of measuring implicit and explicit knowledge of a second language (L2), focusing on grammar. It begins by defining implicit and explicit knowledge in terms of a distinguishing set of criteria. Two ways of investigating implicit knowledge are discussed -- through experimental…

Discusses the L1=L2 hypothesis which states that, all other things except knowledge of language being equal, first language acquisition is the same as second language acquisition. Reviews the evidence for and against the hypothesis, looks at current research and considers the general distinction between formal and informal learning. (SED)