Constructions and Strategies in U niversal D ependencies (2025)

Abstract: Is the framework of Universal Dependencies (UD) compatible with findings from linguistic typology? One way to find out is to investigate whether UD can adequately represent constructions of the world’s languages, as described in William Croft’s recent book Morphosyntax. This paper discusses how such an investigation could be carried out and why it would be useful.

## introduction universal dependencies (ud) is a framework for morphosyntactic annotation, designed to be applicable to all human languages and to enable meaningful cross-linguistic comparisons. the two versions of the guidelines are described in nivre et al. (2016) and nivre et al. (2020); a longer description of the underlying linguistic theory can be found in de marneffe et al. (2021); and annotated data for 168 languages foot_0 can be found together with additional documentation on the ud website. @xcite but can ud really handle the full range of morphosyntactic variation in the world's languages? and is it successful in revealing similarities and differences across these languages in a systematic fashion? one way to approach these questions is to review the ud framework through the lens of linguistic typology. an early attempt to do this can be found in croft et al. (2017), where the authors review version 1 of the ud guidelines and propose a number of improvements for better alignment with typological research findings, some of which were integrated in version 2 of the guidelines. since then, william croft has published the book morphosyntax (croft, 2022), a comprehensive survey of constructions in the world's languages, which brings together the results of sixty years of research on typology and universals and thus provides an excellent basis for a new and more exhaustive review of the ud framework. croft's survey is based on two types of comparative concepts (haspelmath, 2010; croft, 2016): constructions, which are universal form-function pairings defined solely in terms of their function, and strategies, which are non-universal and defined by the pairing of a function with some crosslinguistically identifiable morphosyntactic form. annotations in ud are not defined in terms of constructions and strategies, but for the framework to be universally applicable it must be possible to annotate all major constructions and strategies in the world's languages. and to support cross-linguistic comparisons, these annotations should ideally reflect systematic correspondances in constructions and strategies across languages. the purpose of this position paper is to motivate a more systematic study of these issues, by showing that we currently do not know to what extent ud satisfies these requirements, and to propose a research program to support this investigation. the rest of the paper is organized as follows. in section 2, i give a brief overview of the ud annotation framework, focusing on fundamental design principes; in section 3, i outline the taxonomy of constructions and strategies in croft (2022); and in section 4, i discuss how constructions and strategies are annotated in ud. i conclude that, although the design principles of ud in some respects favor a clear representation of constructions and strategies, the correspondence between the two systems is far from perfect and merits further investigation. ## the ud annotation scheme the ud annotation scheme assumes that words are the basic units of morphosyntax. words encode grammatical information internally through lexical stems and inflectional processes, but since the nature of these processes varies considerably words also enter into syntactic relations with other words, and ud assumes that the information encoded in syntactic structure can be captured by a tree-structured representation consisting entirely of binary relations between words. a subset of these relations correspond to what grammarians would call dependency relations -asymmetric relations between a syntactic head and a dependent -but many of the relations that are necessary for a complete syntactic analysis are essentially symmetrical, even though the tree constraint forces one of the words to be (arbitrarily) chosen as the parent node. by way of illustration, figure 1 shows the ud annotation of an english sentence. @xcite the syntactic analysis in ud assumes that all languages have nominals, which are the primary means of referring to entities, and clauses, which describe events (including actions and states). both nominals and clauses can be further refined by modifiers, which describe attributes of entities or events. figure 1 shows a main clause with the predicate wrote and three nominals: she, a short note, and a pen; there is also an adverbial modifier quickly, modifying the predicate wrote, and an adjectival modifier short, modifying the noun note. a characteristic property of ud syntax is that it prioritizes direct relations between predicates, nominals and modifiers, rather than relations mediated by function words. thus, in figure 1 , there is a direct relation from the predicate wrote to the noun pen, denoting the instrument of writing, while the preposition with is essentially treated as a case marker on the noun. this treatment is motivated by the observation that predicates, nominals and modifiers are more likely to be parallel across languages than function words, which often correspond to morphological inflection (or nothing at all) when comparing across many languages. ## constructions and strategies the most central concept in croft's framework of morphosyntax is that of a construction, which is defined in the following way (croft, 2022, p. 17): construction: any pairing of form and function in a language (or any language) used to express a particular combination of semantic content and information packaging it is worth noting that the functional side of a construction consists of two components, a semantic content and a particular way of packaging the information, also known as a propositional act. this is exemplified in to exemplify the notion of strategy, let us consider the predicate nominal construction, which is "a clause construction defined by the function of predicating an object concept of a referent -that is, asserting what object category the referent belongs to". @xcite two common strategies for this construction are exemplified in ( 1 ) and (2-3). ivan.nom dancer.nom 'ivan is a dancer' the russian example in (1) uses a zero strategy (stassen, 1997), which simply juxtaposes the referring expression ivan with the noun tancor in nominative case expressing the object concept. by contrast, the swedish and english examples in (2) and (3) both use a verbal copula strategy (stassen, 1997), where predication is mediated by a copula verb. the notion of strategy allows us to abstract over language-specific constructions and say that swedish and english use the same strategy, while the russian strategy is different. ## constructions and strategies in ud how are constructions and strategies represented in ud? at first sight, it may appear that they are not represented at all, because the ud annotation is centered on properties and relations of words. to illustrate this, let us return to the predicate nominal construction and consider the ud annotation of (1-3) in figure 2 . all three representations share a structure noun nsubj -→ x, where x can be replaced by any category that can be the head of a referring expression. this captures the fact that the predicate nominal construction involves using a noun as a predicate, which would have been less clear if the copula verb had been treated as the head of the clause in swedish and english. moreover, the fact that swedish and english uses the same strategy is captured by the presence of the structure noun cop -→ aux, which contrasts with the absence of such a structure in russian. in general, strategies often correspond to relations involving function words (like the cop relation). the predicate nominal example suggests that ud representations can be decomposed into distinct substructures corresponding to constructions and strategies. unfortunately, this is not true in ivan tancor propn noun @xmath0: simplified ud annotation for predicate nominal constructions in russian, swedish and english. hänellä on kirja pron aux noun @xmath1. first of all, it is clear that ud representations are more coarse-grained than constructions and strategies, so there will often be a one-to-many mapping from the former to the latter. for example, the substructure that is characteristic of the predicate nominal construction in figure 2 would also be characteristic of an equational construction, as exemplified by ivan is the winner, which in croft's framework is a distinct construction, even though the two constructions often share strategies through a process known as recruitment. more importantly, it is not hard to find constructions where the ud representations completely fail to capture constructional parallelism. one example is the presentational possession construction, defined as "a presentational information packaging of the possession relation in which a possessum is introduced into the discourse, anchored by the possessor" 8 and exemplified in figure 3 with examples in finnish and english. finnish here uses a locational possessive strategy (stassen, 2009), in which the possessum (kirja 'book.nom') is expressed in a subject phrase, and the possessor (hänellä 'her.adess') in an oblique (locative) phrase, with a linking copula verb (on 'be.3sg.pres'). by contrast, english uses a havepossessive strategy (stassen, 2009), where the possessor is expressed in a subject phrase (she), and the possessum in an object phrase (a book), connected by a full transitive verb (has). a closer comparison of the examples reveals that the two representations have next to nothing in common, which could capture the common construction, and also that the two strategies in this case involves 8 https://comparative-concepts.github.io/cc-database/ syntactic relations like nsubj and obj, which in the predicate nominal example were considered elements of the construction. ## a research program for ud which of the two cases discussed above is typical? are ud annotations mostly decomposable into parts corresponding to constructions and strategies, with a few anomalous cases like the presentational possession construction? or is it the latter that is the norm, and the former the exception? at this point, we simply do not know, and this is the main motivation for proposing a research program that systematically investigates how constructions and strategies can be represented in ud, using the survey in croft (2022) as a starting point. more precisely, i propose to develop a constructicon for ud, consisting of the following components: why should we build such a resource and how can we hope to construct it? starting with the why, i believe that a ud constructicon could help us improve cross-linguistic annotation consistency by providing a complementary view of the ud guidelines, which is holistic and onomasiological. it is holistic because it starts from complete constructions rather than particular syntactic relations, and it is onomasiological because it goes from function to (cross-linguistically identifiable) form. this would in particular benefit the annotation of new languages, where guidelines could be developed systematically by first identifying what strategies are used for different constructions. it would also provide better support for construction-based annotation on top of ud, as proposed in weissweiler et al. (2024). last but not least, it would help us find out to what extent ud can represent constructions and strategies systematically and transparently across languages and thereby identify shortcomings in the current guidelines. returning to the question of how to build the constructicon, we can fortunately bootstrap the process by taking the first two components -the inventories of constructions and strategies -directly from croft (2022), or rather from mocca, the database of comparative concepts that is being developed from the glossary of the book (lorenzi et al.). @xcite we can then concentrate on constructing valid ud analyses for all construction-strategy pairs, starting with the most prototypical construction types -reference, modification and predication -and proceeding to non-prototypical cases with more complex variation patterns. examples for all constructions can be found in croft (2022), which contains at least one concrete example for every construction-strategy pair discussed in the book. this should be supplemented with examples from existing ud treebanks, which will allow us to assess the cross-linguistic annotation consistency for different constructions and strategies. ## conclusion in this paper, i have reopened the question of whether ud is an adequate annotation framework from the point of view of linguistic typology, previously raised by croft et al. (2017). i have argued that one way of answering this question is to study more systematically how constructions and strategies, in the sense of croft (2022), can be represented in ud, and i have proposed that this can be done by building a constructicon for ud.