This paper deals with the counterexamples to the general principles that: (1) a sentence as utterance has only one illocutionary force, in the sense of J.L. Austin; and (2) performative verbs do not normally retain illocutionary force in embedded contexts. Various tests for illocutionary force are applied, such as substitution of another speech act within the same syntactic context, co-occurence with modifiers, and comparison with sequences of separate sentences, which constitute independent speech acts. It is proposed that the nearest paraphrase to indirectly expressed speech acts (e.g. May I request...) is a prefatory speech act followed by the "main" speech act, and that such a sequence in discourse may be the source of idiomatic indirect expressions. It is concluded that NP modifiers, such as non-restrictive relative clauses, parentheticals, etc., do retain independent illocutionary force within another speech act, while modifiers of the speech act, such as prefatory clauses, do not. (Author)