Examining the role of explicit phonetic instruction in native-like and comprehensible pronunciation development: an instructed SLA approach to L2 phonology

This paper reports on an instructed second language acquisition study that investigated the effects of explicit phonetic instruction on second language pronunciation by adopting two different outcome measurements (i.e. a rubric of accentedness as well as comprehensibility). Twenty native Japanese learners of English in ESL (English as a second language) settings participated in the current study and were randomly assigned to the experimental group and the control group. After they received four-hour instruction with the target pronunciation features of English-specific segmentals/æ,f,v,θ,ð,w,l,/, the comprehensibility and perceived foreign accent of the participants’ oral production in English were evaluated by four native English listeners. Results suggested that explicit instruction had a significant effect on comprehensibility especially in the sentence-reading task, although a significant reduction in foreign accent was not obtained in any contexts.