Tap and trill clusters in typical and protracted phonological development: Conclusion.

The current issue examined acquisition of challenging segments in complex contexts: Taps/trills in word-initial clusters, plus related targets (/l/-clusters and singleton rhotics and /l/). Data were from preschool children with typical versus protracted phonological development (PPD) in Iceland, Sweden (Germanic), Portugal, Spain/Chile (Romance), Bulgaria, Slovenia (Slavic), and Hungary (Finno-Ugric). Results showed developmental group and age effects. Clusters generally had lower accuracy than singletons, although not uniformly, and were more accurate in stressed syllables. The rhotics were less advanced than alveolar /l/ except in European Portuguese, where the lateral is velarized. In early development, the rhotic is often deleted, but in later, development substitutions for rhotics were more common, primarily non-nasal coronal sonorants, which match some of the place and manner features of the rhotic. Vowel epenthesis sometimes appeared in rhotic clusters. Children with PPD showed more varied mismatch patterns, including more than one mismatch pattern within a cluster. Implications for research and clinical practice are suggested.