Relying on syntax and semantics, the book establishes a three-way structural typology of wh in-situ phrases and extends it to existentials. It pays special attention to the prosodic properties associated with their different readings and proposes an analysis of the distribution of subextraction and pied-piping. Similarly based on semantic and syntactic tests, the book reveals N(egative) words to be universal Quantifiers. It proposes a new structure of N-words in terms of constituent negation and includes a detailed analysis of the difference between not an N and not all the N in French.