The development of flexibility and abstraction in the acquisition of the German ditransitive construction

Abstract According to usage-based accounts of language acquisition, abstract linguistic representations emerge gradually from lexically specific formulas. Higher levels of abstractness are typically associated with increased flexibility, that is, variability in the use of constructions. Developing flexibility can be measured in different ways, e.g., diversity of word use in specific slots of the construction (absolute lexical flexibility), variability in the combination of lexical items (relative lexical flexibility), and the range of semantic meanings expressed within the construction (semantic flexibility). While prior research has mostly focused on the development of flexibility in the verb slot, less is known about how flexibility develops in other slots, and whether different measures of flexibility develop simultaneously or along individual pathways. The present study aims to describe the development of absolute and relative lexical flexibility as well as semantic flexibility in one German-speaking child’s acquisition of the ditransitive construction. The results indicate that lexical and semantic flexibility in the verb slot increase over the course of development. At the same time, the argument slots show considerable flexibility from early on and, contrary to expectations, the construction does not appear to emerge from a small set of highly frequent lexicalized patterns. In particular, conventionalized expressions, which are common in the input, emerge only later in development. The emergence of these lexicalized patterns may in turn support the development of flexibility in other aspects of the construction. These findings suggest that the child acquires both more abstract representations of the construction, as indicated by an increase in flexibility, as well as routinized and highly frequent formulas stored at lower levels of abstraction.