The digital corpuses oblige the researchers to think how to invent new more relevant concepts for their study. We are interested, within the framework of this article, in the question of the multilingualism and its status in the construction of an ethos of the digital citizen or of what Crystal calls a netizen (Crystal, 2001) Through the study of a corpus of tweet collected further to the terrorist attack in Sousse. We aim to understand how are the interactions between the users of the social network Twitter governed by collective linguistic standards? How on-line multilingual linguistic practices participate in the construction of a digital citizenship?