It is well known that native speakers of English around the globe are by far outnumbered today by speakers of English as a second or as a foreign language (Crystal, 2008). English is thus regularly used as a lingua franca, i.e. an intermediary language used between speakers of various linguistic backgrounds, for transnational and intercultural communication in many domains of life (such as business, diplomacy, higher education, tourism, etc.). The study of conditions of using ‘English as a Lingua Franca’ (ELF), intrinsically connected to the fields of World Englishes and Second Language Acquisition (Schneider, 2012), has come to be a booming sub-field and topic of research in English linguistics over the past few years, as is indicated by the publication of a few textbooks, the establishment of a conference series, and the launch of a scholarly journal (JELF). The focus of these approaches has been on the functions, usage conditions, and practical applications of ELF (Seidlhofer, 2011), and also, though to a lesser extent, on any characteristic structural properties (Dewey, 2007; Jenkins, Cogo & Dewey, 2011; Cogo & Dewey, 2012). Clearly, ELF can be found in a wide range of possible applications and contexts, as Cogo & Dewey (2012: 31) have stated: ‘As a natural phenomenon of sociolinguistic variation, ELF includes all types of communicative events, from the transactional to the interactional, and various possible settings, such as the institutional and the casual.’ It is considered to be independent of the interactants' native-speaker status: prototypically ELF involves communication between non-native speakers of English, but sometimes native speakers participate in such encounters as well. It centrally involves accommodation, negotiation and adjustment of forms to achieve successful communication.