There are two types of modal deference expressions which may be superordinate to performative verbs in English: one may ask permission to perform the act or the speaker may express his frame of mind in performing the act. L. argues that these have no illocutionary force of their own: an utterance cannot constitute an intended illocutionary act if there is a conflict in the speaker's pragmatic presupposition between the addressee-authority and the speaker-authority.