ENGLISH
The aim of this study was to find out the types of code mixing and the reasons for using code mixing in Instagram captions, comments, and stories by students class of 2019 at IAIN Syaikh Abdurrahman Siddik Bangka Belitung. The population in this study was all of English Education Study Program students at IAIN Syaikh Abdurrahman Siddik with a total population 153 students. The sample in this study were class 5 A and 5 B students 2019 with a total of 31 students. The method of this study was qualitative method, the researcher used theory proposed by Muysken to find the type of code mixing and Hoffman’s theory for the reasons using code mixing. In collecting the data, the researcher conducted observation and documentation about students’ post in Instagram caption, comments, and stories. Both of the data were calculated with Sudjiono’s formula.
The result showed that there were 197 data of code mixing, 15 data of congruent lexicalization (7.6%), 77 data of alternation (39.1%), and 165 data of insertion (53.3%). While for the reasons for using code mixing there are 161 data, 30 data of being emphatic about something (18.6%), 5 data of quoting somebody else (3.1%), 125 data of talking about particular topic (77.6%), 1 data of repeating word used for clarification (0.7%). Afterwards, the researcher concluded that the types of code mixing used by students was insertion (53.3%) and the most reasons used was talking about particular topic (77.6%)