A Quantitative and Comparative Study of Syntactic Complexity of Subclasses of English Nominal Clauses
Jinlu Liu, Nan Yang, Ming Wu · Journal of Quantitative Linguistics · 2025
This study examines the syntactic complexity of English nominal clauses, utilizing two key metrics – clause type and position – in a corpus-based analysis of 6,481 annotated sentences. The research targets subject, object, appositive, and predicate clauses across American and British English. Findings indicate that: (1) subject and appositive clauses display significantly higher mean dependency distances (MDDs) than object and predicate clauses, pointing to a distinct complexity hierarchy among clause types; (2) extraposition influences syntactic complexity variably by clause type, reducing complexity in extraposed object clauses but increasing it in extraposed subject clauses; (3) sentence length substantially affects the complexity dynamics between clause type, position, and syntactic complexity, with longer sentences intensifying the complexity of specific clause types. Overall, these results offer new perspectives on the intricate relationship between syntactic structures and processing demands in English nominal clauses.