This article presents a series of three experiments investigating the processing of nested epistemic expressions, utterances containing two epistemic modals in one clause, such as "he 'certainly may' have forgotten." While some linguists claim that in a nested epistemic expression one modal is semantically embedded within the scope of…

Questions under Discussion (QUDs) have been suggested to influence the integration of individual utterances into a discourse-level representation. Previous work has shown that processing ungrammatical ellipses is facilitated when the elided material addresses an implicit QUD raised through a nonactuality implicature (NAIs). It is not clear,…