Indonesia’s education trend has been changing substantially in the last 15 years. National Plus and International schools whose medium of delivery is English have mushroomed and the sight of Indonesian children speaking fluent English in public places is no longer rare. The aim of this study is to assess the code-switching conducted by the research participants in four occasions, namely: during lunch break at school, during meal time at home, during family gathering at relative’s house and after Catholic praying school at church. The research participants are three bilingual siblings aged 17 year old, 14 year old and 10 year old. They were asked to record their conversation with their interlocutors in the aforementioned domains. The recording were then transcribed and analyzed to find out the research participant who code-switched most frequently, in which domain code-switching happens most intensively, the functions of code-switching and the matrix language of each research participant. Analysis showed that the youngest research participant produced the most code-switching. Two research participants code-switched the most in family domain during meal time while the oldest one showed a very dynamic code-switching pattern in social domain during school lunch break. All three research participants codeswitched mostly to fill lexical gap in their speech. Finally, the matrix language of the oldest and the youngest research participants is Indonesian while the matrix language of the other one is English. Age of the bilingual children is proven to be influential in the frequency of code-switching. In this case, code-switching is useful in smoothening the communication of the bilinguals. |