Abstract
The purpose of this paper is to clarify the appropriate period for preschoolers to start to study English by focusing on their phoneme production skills in their L1 (Japanese) and L2 (English). 53 five- and six-year-old preschoolers who had not started to formally study English participated in this study. One Japanese vocabulary test (PVT-R) and three pronunciation tests (Japanese, English, and loan words) were conducted. The results showed that their L1 vocabulary age was 7;01 on average, which was nine months above their living age. The participants produced L1 and loan words articulation almost perfectly. Fricatives and plosives showed lower accuracy rates in both the English Pronunciation Test and Japanese Pronunciation Test. In addition, in the English test, lower accuracy rates were found for phonemes such as laterals, semivowels, and some vowels which do not exist in Japanese phonemes. In addition, fronting, lateralization, and spoonerism were observed in Japanese and English tests. Results reveal that the participants’ Japanese pronunciation already had influenced their English pronunciation (i.e., vowel epenthesis) on English phonemes prior to the initiation of official English lessons. Thus, we argue that the age of preschoolers would not be the most appropriate to start English learning in terms of English phoneme production. If young preschoolers have a chance to be taught English, it is necessary to take detailed steps to minimize the influence of Japanese articulation on their English phoneme production.
https://ror.org/01hjzeq58 
