The effects of L1 use on vocabulary acquisition

The last 15 years of L2 acquisition and language education research and literature have seen the emergence of the issue of whether teachers should use the learners’ first language (L1) in foreign or second language (L2) classroom. The interpretation of the debate by teachers and policy makers has impacted on L2 teaching practices. There has been considerable research into teachers’ beliefs about the use of L1, and observing the use of L1 in order to describe its functions in the classroom. Further studies have examined teachers’ and learners’ codeswitching patterns (alternating between the two languages), in order to measure the quantity of L1 use. However, empirical evidence as to the effectiveness, or otherwise, of L1 use is surprisingly lacking in the debate. This study therefore aimed to provide some initial evidence, in order to inform pedagogy, by focusing narrowly on vocabulary learning during teacher-student oral interaction.