Sentence comprehension in German by multilinguals with Norwegian or Polish as L1: Is there cross-linguistic influence from the L1?

The present study compared the comprehension of morphological case in transitive and ditransitive German sentences in two multilingual speaker groups whose first languages (L1s) differ typologically and structurally from the target language: Polish and Norwegian. Like German and unlike Norwegian and English (Germanic languages), Polish (Slavic) has morphological case and a relatively free word order. For all participants, German was the third or even later acquired language, and all had knowledge of English. In a picture selection task, the participants were presented with two event scenes: one that matched the event as described in an auditorily presented sentence and one that mismatched. Critically, successful comprehension required the exploitation of case on full noun phrases (NPs). The results showed that the comprehension of object-initial vs. subject-initial transitive sentences differed between Norwegian and Polish L1 speakers, supporting cross-linguistic influence as a function of structural similarity to the target language. The difference in performance between the object-initial and the prototypical subject-initial order was larger for the Norwegian than for the Polish L1 group, indicating a higher reliance on word order in the former group. The results for the comprehension of different object orders following a ditransitive verb were less conclusive but point in a similar direction. The findings of this study provide new answers to the question under which circumstances there is cross-linguistic influence from other grammar(s) in the comprehension of a later acquired language beyond early stages of acquisition.