Language differentiation in a bilingual child

When four speakers of four different languages interact, the conversation may result in something like: Stephanie (addressing her mother): "Ja chcem tiez takeho vytlacky naplay-doh. " Stephanie's mother (to Stephanie): "Wir mussen Emilies Mama fragen wo sie das gekauft hat. " Stephanie (to Emilie): "Wo kauft das? " Emilie (to Stephanie): "Ich weiss nicht. " Stephanie (to Toni): "Make a slide? " Toni (to Stephanie): "Do you want me to make fly?" Stephanie (to Emily): "Emilie, wo bist du?" Emilie (to Stephanie): " Wos mochstdu da?" Stephanie (to Toni): "This is slide!" Stephanie (to Emilie): "Helikopter, eine... ich mach ' diss. " Emilie (to Stephanie): "Ok, sitz dich da!" Stephanie (to Emilie): "Komm zu mir!" Emilie (to Stephanie): "Ich will Saft." Stephanie 's mother (to Emilie): "Emilie, willst du etwas Saft?" Emilie (to Stephanie 's mother): "Ja." Stephanie 's mother (to Emilie): "Komm, Emilie, ich gebe dir Saft." As the child matures, he or she gradually learns how to differentiate between languages and what code to use in communication with individual people. The aim of this study is to explore the bilingual child's sensitivity for language differentiation, code-switching, code-mixing and translation. It is based on empirical observation, collection of data in the form of a speech diary and on the interpretation of data reflecting language development of primarily one child between 0 and 4 years old and also of several other children 2 to 6 years old immersed in a bilingual or multilingual language environment. Keywords: bilingual education, language differentiation, code-switching, codemixing, translation