Word segmentation plays a crucial role in language acquisition, particularly for word learning and syntax development, and possibly predicts later language abilities. Previous studies have suggested that this ability develops differently across languages, possibly affected by the languages’ rhythmic properties (Rhythmic Segmentation Hypothesis) and target word location in the prosodic structure (Edge Hypothesis). The present study investigates early word segmentation in a language, European Portuguese, that exhibits both stress- and syllable-timed properties, as well as strong cues to both higher-level prosodic boundaries and the word level. Infants aged 4–10 months old were tested with target words located in utterance-medial and utterance-final positions. Evidence for word segmentation was found early in development but only for utterance-edge located target words, suggesting the more salient prosodic cues play a crucial role. There was some evidence for segmentation in utterance-medial position by 10 months, demonstrating that this ability is not yet fully developed, possibly due to mixed rhythmic properties.

This paper focuses on the linguistic competence of adult Portuguese–German bilinguals in their heritage language, European Portuguese (EP), which they acquired at home in early childhood in the context of German as the majority language. Based on a grammaticality judgment test, we investigate their morphosyntactic knowledge of clitics. The central questions are whether possible deviations from native monolinguals may be traced back to a) lack of contact with the formal register; b) reduced input after preschool age; and c) cross-linguistic influence. The results reveal qualitative differences between the heritage speakers and a group of monolingual controls in almost all test conditions. We conclude that although the linguistic knowledge of the heritage bilinguals investigated in this study differs from that of monolinguals, it is not “deficient” but “different” and “innovative”, because it is primarily based on the spoken variety of the language and because it promotes linguistic changes which are inherent in the speech of native monolinguals.