Title: On the development of nominal and verbal morphology in four lusophone creoles
Abstract

Abstract
Bidirectional case markers in West African languages, including those of
the Songhay family, are morphemes inserted between subject and object NPs that
would otherwise be adjacent. They therefore specify both that the NP to the left is
a subject, and that the NP to the right is an object, and they cannot be bracketed
uniquely with either. This is shown by the fact that these morphemes are absent when
either subject or object position is (structurally and phonologically) absent, for exam-
ple due to extraction. This is the only morphological case-marking in the relevant
languages. The operation inserting such morphemes must have reference to constit-
uent structure (NP), abstract case (subject, object), and linear adjacency. These data
increase the evidence that complex case-marking operations can apply in a centrally
located morphology component that has simultaneous access to categorial and linear
relations. The idea is questionable that such morphological operations take place at a
syntax/PF interface, where syntactic categories are first aligned with prosodic phrases,
since actual prosodic (e.g. accentual) bracketings do not always coincide with the
bracketings relevant to case morphology. This point is made with data from Tam-
ashek (Berber) nominal prefix alternations, preceding the main section on Songhay
case marking.