The aims of the present study were twofold. The study addressed the issues of simultaneous attention to form and meaning in second language (L2) written input and reactivity of think-alouds. Specifically, the study examined the comprehension of L2 learners of Spanish who either attended to lexical or grammatical forms while reading for meaning or read for meaning alone. Learners completed these tasks while either thinking aloud or not. Results indicated only a minimal effect for thinking aloud that did not appear to compromise the internal validity of the study. Additionally, results showed that attending to grammatical or lexical form while reading for meaning did not affect comprehension. Indeed, learners who processed these forms more deeply evidenced greater comprehension. These findings are considered in light of methodological issues and the larger issue of simultaneous attention to form and meaning in a L2.

This article addresses methodological concerns in research on grammatical aspects of code-switching. Data from code-switching have the potential for a unique contribution to linguistics by giving us access to combinations of linguistic features that may be difficult (or impossible) to observe in monolingual data. Nonetheless, the use of code-switching data for linguistic inquiry is not without issues. In this paper, we focus on three methodological questions specific to code-switching research: (i) project design, (ii) experimental procedure and (iii) participant selection. Drawing on experimental data from both published works and in-progress projects, we highlight potential solutions to each methodological challenge, concluding that several solutions are often required to mitigate the impact of confounding variables. In line with previous work (e.g. Grosjean 1998, Gullberg, Indefrey & Muysken 2009), we suggest that researchers clearly report on their methodology. Our overall goal is to contribute to a dialogue on best practices in code-switching research.

Many languages, including English, exhibit a restriction on subject extraction over complementizers called the that-trace effect. Although extensively studied, this phenomenon remains a puzzle. Not all languages exhibit the effect; Spanish does not. Spanish also allows postverbal subjects, while English does not, which has been linked to the that-trace effect. Because Spanish/English differ in these properties, combining lexical items from both languages in a single derivation, as in code-switching, offers additional insight into the nature of the restriction. Two acceptability judgment tasks of Spanish/English code-switching reveal that a single Spanish functional head is insufficient to license either postverbal subjects or subject extraction. Instead, we argue, the that-trace effect and related properties arise from the interaction of two heads.

Among methodological concerns specific to code-switching (CS) research is the design of the target stimuli used in experiments with an acceptability judgment task. We argue here that research which makes use of CS data of this type must also incorporate monolingual stimuli into the experimental design, specifically monolingual stimuli judged by the same bilingual participants who judge the code-switched stimuli. We do so by reviewing two sets of experimental CS data we collected and exploring the role that monolingual stimuli can play in the analysis of that data. In each experiment, an analysis based solely on acceptability judgments of the CS stimuli leads to one interpretation, while incorporation of results from the monolingual stimuli leads to a distinct interpretation. We show that it is the interpretation integrating the monolingual acceptability judgments which is more valid, thereby arguing for the value of monolingual stimuli in design and analysis.