Pair work activities support natural communication and facilitate students' selfdirected learning (Johnson & Johnson, 1992). Recently, negotiation of form and meaning through peer-interaction during the pair/group work is found facilitative in second language acquisition (Long, 1996; Swain & Lapkin, 2001; Pica, 2008). However, little is known about its effectiveness in Japanese language settings since preceding researches are grounded on Indo-European language settings. Therefore, the data from the tasks performed in actual Japanese classes were analyzed to investigate this argument.

The speech length, accuracy, and complexity, as well as the number of language related and form-meaning negotiation episodes, were analyzed using 12 hours of recorded data from the intermediate and advanced levels. The results show that the higher proficiency learners produced more complex but less accurate utterances. The speech length is affected by the task types rather than the proficiency levels. In addition, intermediate and advanced learners paid little attention to forms during pair and group work.