This study investigates the thematic structure of Persian imperative clauses within the framework of Systemic Functional Grammar (SFG), focusing on the concept of Theme. In this framework, the Theme is defined as the first element of a clause that is a Participant, a Process, or a Circumstantial adjunct. In Persian, the unmarked Theme in most constructions follows the pattern of declarative clauses; however, the thematic position in imperative clauses has been little studied. To address this, 2,099 imperative clauses were extracted from the Persian Syntactic Dependency Corpus, and half of them were analyzed for thematic structure. It was hypothesized that in some clauses—particularly those with motion verbs—the verb might serve as the unmarked Theme. The findings reveal that more than 90% of Persian imperatives are verb-final. In about 10% of the clauses, a verb with a clausal complement appears initially, with its complement at the end. Among these, only about 0.5% are simple clauses in which the verb itself occurs in the initial position. Overall, the results show that the thematic pattern of Persian imperative clauses conforms to the verb-final typology of the language.IntroductionSystemic Functional Grammar (SFG) conceptualizes grammar as a meaning-oriented system shaped by social use. Within this framework, each clause simultaneously realizes three metafunctions: experiential, interpersonal, and textual. The experiential metafunction is concerned with processes, participants, and circumstances, while the interpersonal metafunction organizes relations between speakers and addressees; and the textual metafunction organizes the clause as a message in discourse.Central to this metafunction is the notion of Theme, which identifies the element chosen as the point from which the clause unfolds. Thematic choices reflect how speakers manage information flow, relate clauses to their context, and guide addressees toward an intended interpretation. As such, the analysis of thematic structure provides insight into the interface between grammar, discourse, and communicative intent.Cross-linguistic research has shown that unmarked thematic patterns often vary according to clause type. In imperative clauses, for example, most languages display subject omission as a conventional strategy. In English, this pattern typically coincides with verb-initial imperatives, where the Process functions as the unmarked Theme. Persian, however, differs typologically as a verb-final language, raising questions about how imperative clauses are thematically organized within its grammatical system.Although word order and thematic structure in the Persian language have been widely discussed for declarative and interrogative clauses, imperative constructions have received comparatively little systematic attention. This gap is noteworthy given the frequency of imperatives and their central role in instructional, persuasive, and interpersonal discourse.Assuming subject omission in imperative clauses as a cross-linguistic common pattern, the present study focuses on how thematic structure is realized in Persian imperatives. It examines whether the unmarked thematic pattern of Persian declarative clauses extends to imperatives and whether the Process can function as the unmarked Theme, as observed in English. By addressing these questions, the study seeks to identify the unmarked thematic structure of Persian imperative clauses through a corpus-based analysis.Research QuestionsThis study addresses the following research questions:Does the unmarked thematic pattern of Persian declarative clauses extend to imperative clauses?Can the Process (verb) function as the unmarked Theme in Persian imperative clauses, as it does in English?Literature ReviewStudies of word order have long been shaped by typological research, notably the work of Greenberg (1963, 1974), Dryer (1992), and Bybee (2002), which seek to explain cross-linguistic ordering patterns in functional terms. Functional approaches treat word order as a flexible means of organizing discourse rather than a purely syntactic constraint, emphasizing its role in information management and contextual interpretation. Research on Persian has largely concentrated on declarative and interrogative clauses, showing that verb-final order is predominant but readily modified for discourse-related purposes (Dabir-Moghaddam & Sharifi, 2005; Rezaei & Tayyeb, 2006; Tabatabaei & Modarresi, 2017). Corpus-based studies of Persian Wh-questions further indicate that unmarked thematic patterns in Persian differ from those in English and vary according to clause type (Mirzaei, 2019). Despite these advances, the thematic structure of imperative clauses in Persian has received little systematic attention.MethodologyThe data for this study were extracted from the Persian Syntactic Dependency Treebank (Rasooli, et al., 2013). Using verbal mood annotations, 2,099 imperative clauses were identified. From this dataset, 1,276 clauses were selected sequentially for detailed analysis. Each clause was examined for word order and coded for the presence and position of the Process, Participants, Circumstantial adjuncts, and vocatives. This approach allowed for a quantitative and qualitative analysis of thematic patterns in Persian imperative clauses.ResultsThe analysis shows that the vast majority of Persian imperative clauses are verb-final. Verb-initial structures are rare and largely restricted to clauses containing clausal complements.Figure 1Position of the verb in Persian imperative clausesIn verb-final imperatives, Circumstantial adjuncts are the most frequent unmarked Themes, followed by Participants. Figure 2Ordering of circumstances in relation to direct and indirect objectsVocatives typically occur in the initial position but do not function as Themes. The modal adjunct lotfan, ‘please’ appears frequently at the beginning of clauses, but does not alter the underlying verb-final thematic structure. DiscussionThe findings show that Persian imperative clauses differ fundamentally from their English counterparts in thematic structure. The strong preference for verb-final structures reflects broader typological constraints and suggests that thematic choices in the Persian language are shaped primarily by language-specific syntactic patterns rather than by clause type alone. The prominence of Circumstantial adjuncts as Themes highlights the role of contextual framing in Persian directive discourse.ConclusionThis study demonstrates that the unmarked thematic structure of Persian imperative clauses conforms to the verb-final typology of the language. The Process does not function as the unmarked Theme, even in clauses with motion verbs. Instead, non-verbal experiential elements—particularly Circumstantial adjuncts—are favored in the thematic position. These findings contribute to functional and typological studies of Persian and open new avenues for research on the interaction between thematic structure, modality, and polarity in imperative constructions.