Restructuring dynamic mapping of L1 resources in L2 development with bilingual metacognitive instruction: The case of sentence stress

Aims and objectives/purpose/research questions: This study aims to investigate the role of metacognition in regulating bilingual speakers’ dynamic use of linguistic resources across languages. In particular, it examines how first language (L1) and second language (L2) metacognition influence Mandarin-speaking L2 English learners’ development of sentence stress. Design/methodology/approach: Forty-eight high-proficiency Mandarin-speaking L2 English learners were randomly assigned to four groups with different instructional conditions: (1) imitation-repetition with no metacognitive components, (2) monolingual metacognitive instruction in L2, (3) bilingual metacognitive instruction bridging L1 and L2, and (4) control group. Each participant took a pretest, a posttest, and a 2-week delayed posttest to evaluate their use of sentence stress in both control and extemporaneous conditions. Semi-structured interviews were conducted after the instruction. Data and analysis: Six trained native English-speaking raters assessed the perceivability and placement of sentence stress using 9-point Likert-type scales. Acoustic measures of pitch range, pitch height, duration, and intensity were extracted via a speech analysis software program. Quantitative data were analyzed using linear mixed-effects models. The interview data were examined through a thematic analysis. Findings/conclusions: Both monolingual and bilingual metacognitive instructions facilitated learners’ sentence stress development in a controlled, read-aloud task. However, only participants receiving bilingual metacognitive instruction demonstrated statistically significant improvement in extemporaneous speech and reported spontaneous use of sentence stress in everyday communication. Originality: This is the first study to systematically investigate how L1 and L2 metacognition influence the development of sentence stress. It is also the first study to provide empirical support for bilingual metacognitive instruction in L2 pronunciation instruction. Significance/implications: This study highlights the foundational and multidimensional role of metacognition in bilinguals’ regulation of linguistic resources across languages. It also provides empirical support for bilingual and multilingual pedagogical practices that leverage learners’ full linguistic repertoires as resources in second language acquisition (SLA).