Notwithstanding their potential for novel approaches to language teaching and learning, Virtual Worlds (VWs) present numerous technological and pedagogical challenges that require new paradigms if the language learning experience and outcomes are to be successful. In this presentation, we argue that the notions of presence and affordance, together with the time/space dimensions of interactions in virtual worlds (e.g. Bakhtin's (1981) chronotope, Foucault's (1984) heteropia, and Lemke's (2000) heterochrony), provide new insights into language learners' trajectories as they attempt to carry out tasks that are designed to make use of virtual worlds' characteristics and potentialities. We explore and analyse a critical incident that occurred during the realisation of a language learning task by university learners of Italian in Second Life©. Recordings of the session, teacher observations, learner reflections and interviews have provided large amounts of data highlighting a number of critical incidents that emerged during their execution. Analysing these critical incidents through the lenses of presence, affordance, and time/space inseparability allows us to highlight the non-linearity of temporal and spatial aspects of interactions in virtual worlds, and to reveal the emergence of affordances and learning chronotopes linked to such interactions. In turn, the analysis of these emerging learning chronotopes helps us refine the design and implementation of language learning tasks in virtual worlds. [For full proceedings, see ED565044.]