In Persian grammar, the Sentences Theory is the study of sentence structure and the rules governing the arrangement and relationship of words and phrases within a sentence.

The Sentences Theory in Persian grammar is based on the principle of verb-subject-object (VSO) word order. This means that the sentence typically starts with the verb, followed by the subject and then the object. However, Persian is a flexible language and allows for variation in sentence structure. For example, the subject can be placed at the beginning of the sentence for emphasis, or the verb can be omitted if its meaning is obvious from the context.

Another important aspect of the Sentences Theory is the use of case markers. Persian has no grammatical case system, but it uses prepositions and postpositions to indicate the relationship between words in a sentence. These case markers determine the role of the noun or pronoun in the sentence, such as subject, direct object, indirect object, or possessor.

Understanding the Sentences Theory in Persian grammar is essential for constructing well-formed and meaningful sentences. It allows learners to express their thoughts clearly and accurately in writing and conversation.