Аннотация:This paper deals with the conceptual semantics and the discourse functions of Spanish epistemic adverbs and/or adverbial phrases such as quizá , tal vez , a lo mejor , igual , lo mismo ‘maybe/perhaps’ in informal conversation. The study is based upon the following hypothesis: the best basis for a modal adverb to be ‘successful’ in spontaneous conversation is having a ‘dynamic’ semantic profile with an ‘instructional’ role in speaker-participant interaction. It will be shown that the conceptual profiles of grammaticalized adverbial expressions such as a lo mejor allow for specific interactional functions in conversation. The argument is corroborated by striking semantic and frequency differences with the less grammaticalized but more productive modal adverbs ending in - mente ( posiblemente and probablemente ). My corpus analysis also indicates that, from an interactional point of view, a lo mejor , igual and lo mismo have consistent discourse functions which quizá(s) and the adverbs in -mente clearly lack.
