This article explores systematic differences between French and English in the syntax of sentence negation, questions, adverbs, floating quantifiers, and quantification at a distance. The author suggests that these differences can be correlated and deduced from the structure of Universal Grammar (UG) and the "opacity" or "transparency" of Agreement (Agr) in French and Modern English. The analysis focuses on the structure of the IP ( intermediate phrase) and introduces a more articulated approach to its components, including Infl (inflection) and AgrP ( Agreement projection). The author argues that Infl should not be considered as a single constituent with two different sets of features but rather as two maximal projections, each with its own set of features. The article also discusses the role of the Empty Category Principle (ECP), θ-theory, and quantification theory in understanding these syntactic phenomena. The author provides empirical arguments for the proposed analyses and addresses several problems and questions that arise from the comparison of French and English, including the lexical restrictions on Verb Movement and the status of auxiliary verbs.This article explores systematic differences between French and English in the syntax of sentence negation, questions, adverbs, floating quantifiers, and quantification at a distance. The author suggests that these differences can be correlated and deduced from the structure of Universal Grammar (UG) and the "opacity" or "transparency" of Agreement (Agr) in French and Modern English. The analysis focuses on the structure of the IP ( intermediate phrase) and introduces a more articulated approach to its components, including Infl (inflection) and AgrP ( Agreement projection). The author argues that Infl should not be considered as a single constituent with two different sets of features but rather as two maximal projections, each with its own set of features. The article also discusses the role of the Empty Category Principle (ECP), θ-theory, and quantification theory in understanding these syntactic phenomena. The author provides empirical arguments for the proposed analyses and addresses several problems and questions that arise from the comparison of French and English, including the lexical restrictions on Verb Movement and the status of auxiliary verbs.