(PhysOrg.com) -- An historical study of the development of irregular verbs in the hundreds of Romance languages including French, Spanish, Italian, Portuguese, Romanian and Catalan has revealed how these structures survive. Experts have also examined why they are learned by successive generations despite making no sense or, apparently, having any function in the language.

Oxford University has published an online database displaying the irregularities of the verb systems of 80 Romance languages and dialects - those that developed from Latin - to highlight the research. The database is useful to specialists and others with an interest in Romance languages.

Professor Martin Maiden of Oxfords Faculty of Linguistics Philology & Phonetics and the Faculty of Medieval and Modern Languages led the four year study which was funded by the Arts and Humanities Research Council.

He said: Many people will remember groaning at school when faced with irregular French or Spanish verbs and wondering why they were the way they were. Our work helps to explain why they, and their equivalents in many related languages, not only exist but are even reinforced and replicated over time.

There is usually a good historical reason why irregularities appear in a language, Professor Maiden adds, but often the original causes disappear, leaving behind apparently inexplicable irregularities.

Quite often, subsequent generations of speakers simply eliminate these irregularities. But what we have found is that an alternative strategy is to keep the irregularity yet seek to make its occurrence and distribution as predictable as possible, through spreading and various kinds of reinforcement of the irregular pattern'.

Some forms of the French verb mourir (to die) have the spelling eu rather than ou (for example je meurs  I die - against nous mourons  we die. This difference is due to sound changes at an earlier stage of the language but the pattern of irregularity created by these changes then provides a template into which other kinds of irregularity, which cannot be explained by sound change, are attracted.

The irregular forms of the verb aller (to go, for example je vais  I go - against nous allons - we go) can be shown to have followed this pattern.

Professor Maiden believes that the Romance languages provide an extraordinarily rich and detailed field for the study of how and why language changes.

Our research has opened up numerous new avenues of investigation, which we are already actively pursuing, and has shown that many Romance varieties too often neglected in mainstream Romance linguistics (such as Romanian or the French spoken on the Atlantic coast of Canada) have fascinating properties which we want to explore further.

Professor Maiden, John Charles Smith, also of Oxfords faculties of linguistics and modern languages, and Marc-Olivier Hinzelin of the University of Hamburg are now working on a book detailing the research findings and their significance. The Romance Verb: Autonomous Morphology in Paradigm Change is due to be published next year by Oxford University.

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