抄録
This study used a survey to investigate how Japanese graduate students select their Japanese speech style based on their relationships with laboratory colleagues, including international peers. The findings revealed that these students employed different speech style when interacting with international students compared to their Japanese counterparts. When the formal "desu/masu" style was chosen, it reflected a sense of psychological distance and linguistic convergence to match the international student's style. Conversely, even when the casual style was adopted, similar to interactions with Japanese students, international students were perceived to having challenges in using the formal "desu/masu" style.
https://ror.org/048nxq511 
