Westergaard's microcue account raises the question of the exact nature of language transfer in the acquisition of languages as well of how L1/Ln input interacts with the principles of universal grammar (UG) during processing. In order to consider in more detail the actual representation building, processing mechanisms that would be involved, her…

In her keynote article advocating the Linguistic Proximity Model for third language (L3) acquisition, Westergaard (2021) presents several arguments against 'copying and restructuring' in nonnative language acquisition, mechanisms central to Schwartz and Sprouse's (1996) Full Transfer/Full Access model of second language (L2) acquisition. In this…

This commentary discusses the recent keynote article in "Second Language Research" by Westergaard (2021), which extends the Micro-cue Model to second language (L2) and third language (L3) acquisition. The commentary comments on such questions as: What makes a given property easy or hard to acquire? How do learners determine similarity?…

In this commentary, I suggest that it may be helpful to think about the formidable problem space that Westergaard's (2021) Linguistic Proximity Model seeks to address at the three levels of analysis that Marr (1982) famously proposed are needed to understand any complex cognitive system. I argue that at the computational level of analysis, where…

In this article, I argue that first language (L1), second language (L2) and third language (L3) acquisition are fundamentally the same process, based on learning by parsing. Both child and adult learners are sensitive to fine linguistic distinctions, and language development takes place in small steps. While the bulk of the article focuses on…

Amaral and Roeper (this issue; henceforth A&R) argue that all speakers -- regardless of whether monolingual or bilingual -- have multiple grammars in their mental language representations. They further claim that this simple assumption can explain many things: optionality in second language (L2) language behaviour, multilingualism, language…

Optionality is a central phenomenon in second language acquisition (SLA), for which any adequate theory must account. Amaral and Roeper (this issue; henceforth A&R) offer an appealing approach to it, using Roeper's Multiple Grammars Theory, which was created with first language in mind but which extends very naturally to SLA. They include…

This article clarifies some ideas presented in this issue's keynote article (Amaral and Roeper, this issue) and discusses several issues raised by the contributors' comments on the nature of the Multiple Grammars (MG) theory. One of the key goals of the article is to unequivocally state that MG is not a parametric theory and that its…

The central claim in Amaral and Roeper's (this issue; henceforth A&R) keynote article is that everyone is multilingual, whether they speak one or more languages. In a nutshell, the idea is that each speaker has multiple grammars or "sub-sets of rules (or sub-grammars) that co-exist". Thus, rather than positing complex rules to…

This paper presents an extension of the Multiple Grammars Theory (Roeper, 1999) to provide a formal mechanism that can serve as a generative-based alternative to current descriptive models of interlanguage. The theory extends historical work by Kroch and Taylor (1997), and has been taken into a computational direction by Yang (2003). The proposal…

The article by Amaral and Roeper (this issue; henceforth A&R) presents many interesting ideas about first and second language acquisition as well as some experimental data convincingly illustrating the difference between production and comprehension. The article extends the concept of Universal Bilingualism proposed in Roeper (1999) to second…

Contraction of "want to" to "wanna" is subject to constraints that have been related to the operation of Universal Grammar. Contraction appears to be blocked when the trace of an extracted "wh"-word intervenes. Evidence for knowledge of these constraints by young English-speaking children has been taken to show the operation of Universal Grammar…

This article examines the third language (L3) developing morphology of 78 Basque-Spanish bilinguals following a Content and Language Integrated Learning (CLIL) program and a mainstream English as a foreign language (non-CLIL) program. The analysis of cross-sectional and longitudinal oral data shows that (1) the omission of inflection in the L3…

Four recent volumes on acquisition of French by different populations cover a range of areas, particularly the development of verbal tense/agreement and nominal gender/concord in first language (L1) acquirers, as opposed to second language (L2) learners; the generalizability of grammatical deficits (e.g. difficulty acquiring parametrized features…

Researchers who assume that Universal Grammar (UG) plays a role in second language (L2) acquisition are still debating whether L2 learners have access to UG in its entirety (the Full Access hypothesis; e.g. Schwartz and Sprouse, 1994; 1996; White, 1989; 2003) or only to those aspects of UG that are instantiated in their first language (L1) grammar…