Studia Logica

, Volume 87, Issue 2, pp 295–321

Commutation-Augmented Pregroup Grammars and Mildly Context-Sensitive Languages


DOI: 10.1007/s11225-007-9088-z

Cite this article as:
Francez, N. & Kaminski, M. Stud Logica (2007) 87: 295. doi:10.1007/s11225-007-9088-z


The paper presents a generalization of pregroup, by which a freely-generated pregroup is augmented with a finite set of commuting inequations, allowing limited commutativity and cancelability. It is shown that grammars based on the commutation-augmented pregroups generate mildly context-sensitive languages. A version of Lambek’s switching lemma is established for these pregroups. Polynomial parsability and semilinearity are shown for languages generated by these grammars.


Formal language theorypregroup grammarsmildly context-sensitive languages

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  1. 1.Department of Computer ScienceTechnion-Israel Institute of TechnologyHaifaIsrael