摘要：New forms of communication that have recently developed in the context of Web 2.0 make it necessary to reconsider some of the analytical tools of linguistic analysis. In the context of keyboard-to-screen communication (KSC), as we shall call it, a range of old dichotomies have become blurred or cease to be useful altogether, e. g. "asynchronous" versus "synchronous", "written" versus "spoken", "monologic" versus "dialogic", and in particular "text" versus "utterance". We propose alternative terminologies ("communicative act" and "communicative act sequence") that are more adequate to describe the new realities of online communication and can usefully be applied to such diverse entities as weblog entries, tweets, status updates on social network sites, comments on other postings and to sequences of such entities. Furthermore, in the context of social network sites, different forms of communication traditionally separated (i. e. blog, chat, email and so on) seem to converge. We illustrate and discuss these phenomena with data from Twitter and Facebook.
