Relationships between linguistic theory and L1 grammar education revisited: a Delphi study on the key metaconcepts in the syntax-semantics interface

Abstract This Delphi study investigates whether linguists from diverse theoretical backgrounds can reach consensus on core metaconcepts at the syntax–semantics interface, and how these metaconcepts are perceived as interconnected within linguistic theory and education. Expanding on a previous study conducted primarily with Dutch experts, this research draws on an international sample of 58 linguists across generative, cognitive and functional traditions. Through iterative Delphi rounds and Perceived Causal Network analysis, participants evaluated and refined a shared set of metaconcepts and their perceived relationships. The study identifies a stable core of foundational metaconcepts valued across theoretical traditions and shows that the perceived importance of 23 metaconcepts is largely reproduced from the earlier study, despite the broader linguistic and theoretical diversity of the current expert group. Structural metaconcepts continue to be rated as the most important ones for both theoretical linguistics and language education. The network analyses further illuminate how experts view interdependencies among key metaconcepts, revealing several that function as threshold concepts and may need to be acquired before others can be fully understood. These findings strengthen the validity of a metaconceptual approach to grammar teaching, in which the school grammar curriculum is enriched with metaconcepts that are relevant in linguistic theory. Ultimately, the study helps bridge divisions between theoretical schools of thought and between linguistics and grammar education, offering a shared and empirically grounded foundation for developing learners’ metalinguistic understanding.