As one might expect, motivational theorists have attempted to explain motivation in different ways. This case study at-tempts to provide relevant evidence for the contribution of motivation in second language learning by looking at the success of Japa-nese study of an adult who learned Japanese at a later age 24, acquiring the target language over a 5-year period characterized bytotal exposure in Japan. The study shows that adult can still be successful to acquire second language if he is exposed to the envi-ronment and has strong motivation, and that the boundary of integrative motivation and instrumental motivation is not necessarilyclear-cut completely.
