Dr Seuren's study deals with the problem of presenting an adequate model of grammatical description. The model he proposes conforms in its main outlines to the transformational generative grammar established by Chomsky, but differs in important respects. These mainly affect that part of Chomsky's syntactic component known as the 'base', which generates basic or 'deep' structures. In the model of the base proposed here two main constituents are distinguished for every deep structure representation of a sentence, vis-a-vis the operators and the nucleus. The deep structure of a sentence is thus seen to be very similar to the logical structure of a proposition. The arguments given in support of this analysis are based on mainly on considerations of simplicity and semantic adequacy.