NET-BASED DESCRIPTION OF MODALITY IN NATURAL LANGUAGE (ON THE EXAMPLE OF CONDITIONAL MODALITY)

The intention of the present paper is to show how the Petri nets formalism can be applied for explaining not only temporal but also modal properties of sentences in natural languages. A special attention has been paid for distinguishing courses of actions with forking (that creates different, but coexistent courses) from branching (that creates different and mutually exclusive courses). It is argued that conditional sentences cannot be represented properly by means of logical implication; instead, for this representation the net description is proposed. Examples serve to show how Petri nets can be viewed as a universal tool (an intermediate language) for analyzing and comparing different natural languages.