Southeast Asia, as we know, is highly multilingual: there are few, if any people in the region who communicate in only one “language”. The majority, including the population of Brunei Darussalam (both residents and migrant workers) habitually use two or more languages on a daily basis. Usually these are a variety of Malay and a variety of English, but many other languages are also in the mix. Many people have more than two languages as part of the repertoire, and are able to draw on these according to expediency. This talk gives examples of words and phrases which cross the boundaries between languages, such as “polis”, “fail”, “teknologi”, “gibap” (give up), “mutubut” (motor boat). This leads us to ask whether the notions of first and second languages are still valid, and whether these should be challenged. But if there are no fixed boundaries between them, how can languages be described and classified? Dr James McLellan is an Associate Professor in the English Studies programme, Faculty of Arts and Social Sciences, Universiti Brunei Darussalam. His research interests include the languages of Borneo, mixed language use in social media, and varieties of English in southeast Asia. He is currently working on a book which challenges the whole concept of separate and distinct languages. This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at https://www.ted.com/tedx