<i>Speakst Du English?</i> Morphological Code-Mixing in German–English Bilingual Children

Aims: This study investigates morphological code-mixing, the combination of morphemes from two languages within a single word, in the spontaneous speech of young German–English bilingual children. Following a usage-based perspective, the study asks whether children’s morphological code-mixing shows systematic patterns and whether these patterns reflect properties of the linguistic input they receive. Method: The analysis is based on longitudinal corpus data from three German–English simultaneous bilingual children aged 2 to 3 years. All children were raised in Germany in families following a one-parent–one-language approach, but their input conditions differed in the relative frequency and distribution of German and English. Utterances were coded for language type and analyzed for instances of morphological code-mixing. Data and Analysis: Across the three corpora, 696 instances of morphological code-mixing were identified. Each mixed form was coded for type of mixing, part of speech, language of stems and affixes, and grammatical categories realized in inflectional mixing. Quantitative comparisons were conducted across children to examine distributional patterns and effects of differing input conditions. Findings: Morphological code-mixing appeared in fewer than 2% of utterances but was produced by all children. Individual differences emerged in both frequency and types of mixes. Inflectional mixing was the most common pattern, especially German inflectional morphemes attached to English stems. Children with more balanced or shifting input conditions also produced German stems with English inflectional markers. Mixed compounds occurred in both German–English and English–German configurations. These patterns mirrored the children’s input distributions and developmental shifts in language proficiency. Originality: The results support a usage-based account in which morphological code-mixing arises from entrenched morphological frames and analogical extension rather than violations of grammatical constraints. Significance/Implications: The study shows that morphological code-mixing in early bilingual development is systematic, input-sensitive, and shaped by children’s experience with partially schematic constructions across their two languages.