Applied linguistics may benefit from a morphological complexity measure to get a better grip on language learning problems and to better understand what kind of typological differences between languages are more important than others in facilitating or impeding adult learning of an additional language. Using speaking proficiency scores of 9,000…

This study reports on the impact of 11 West European first languages on the acquisition of Dutch. Using data from nearly 6,000 second-language learners, it was found that the mother tongue had a rather large impact on two language skills--namely, oral and written proficiency--as measured by the scores received by these learners on the State…