Age as a factor determining effectiveness of L2 acquisition




age of onset, rate of acquisition, ultimate attainment, naturalistic L2 learning, instructed L2 learning


A common belief is that the earlier we begin learning a language, the better chance we have at mastering it. Some push this belief further, suggesting that after one reaches a certain critical age the odds of succeeding at attaining high proficiency in L2 are dropping dramatically. However, research remains inconclusive regarding not only at what age these cut off points should be, but also whether they are indeed a fact. Nevertheless, learners, teachers and policy makers tend to repeat after Krashen et al. (1979) that “adults and older children in general initially acquire the second language faster than young children (older-is-better for rate of acquisition), but child second language acquirers will usually be superior in terms of ultimate attainment (younger-is-better in the long run)” (p, 574). This article examines historical and recent empirical evidence gathered in relation to the views that age earlier onset of L2 acquisition impacts the ultimate attainment of the learner, and explore why older learners are seen as those learning faster. It also points out at an oversight regarding the comparison between younger and older learners without considering the setting in which the language acquisition takes place. Finally, pedagogical implications of juxtaposing the empirical evidence with the views often cemented in the mentality of students, teachers and policy makers are presented.


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Author Biography

Katarzyna Li, University of Oxford

Katarzyna Li (née Jasinska-Belfort) is a polyglot and a language teacher. She has been teaching English, German and French as first and foreign languages in various academic settings for over 10 years in Japan, Poland, Brazil, Hong Kong, UK and Switzerland. She graduated Computer Science at the University of Southern Denmark, obtained PGCE in Modern Foreign Languages from University of Manchester, and is currently completing her MSc in Applied Linguistics at the University of Oxford. Her research interests include neurology of L2 acquisition, child multilingualism, vocabulary acquisition, factors that affect one’s ability to attain high proficiency in L2, and statistical data analysis in context of education-related research.


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How to Cite

Li, K. (2023). Age as a factor determining effectiveness of L2 acquisition. Journal of Language Teaching, 3(9), 8–13.