Table of Contents -- Acknowledgements -- Introduction -- Section I: Theoretical Issues -- Parentheticals and the grammar of complementation -- On theticals: A "rootless" analysis of I think -- Speaker and quote reduced parenthetical clauses -- On V2, gaps, and operators in comment and reporting parentheticals -- Section II: Diachronic and ontogenetic development -- An approach to parenthetical courtesy markers in requests in Late Modern English -- Origin and development of French parenthetical verbs -- Ontogenetic paths to the parenthetical construction -- Section III: Prosody and its interfaces -- Epistemic Parenthetical Verb Phrases: CCommand, Semantic Scope and Prosodic Phrasing -- Are reporting clauses special cases of parentheticals? -- Mapping to prosody: Not all parentheticals are alike -- The Vocative in European Portuguese: Prosodic Effects of its Position in the Sentence -- Index.