  Formal work in linguistics has both produced and used important mathematical
tools. Motivated by a survey of models for context and word meaning, syntactic
categories, phrase structure rules and trees, an attempt is being made in the
present paper to present a mathematical model for structuring of sentences from
active voice to passive voice, which is is the form of a transitive verb whose
grammatical subject serves as the patient, receiving the action of the verb.
  For this purpose we have parsed all sentences of a corpus and have generated
Boolean groups for each of them. It has been observed that when we take
constituents of the sentences as subgroups, the sequences of phrases form
permutation roups. Application of isomorphism property yields permutation
mapping between the important subgroups. It has resulted in a model for
transformation of sentences from active voice to passive voice. A computer
program has been written to enable the software developers to evolve grammar
software for sentence transformations.
