In this study, we investigated how children produce wh-questions in five languages: German, Hungarian, Malayalam, Mandarin, and Yoruba.
These languages represent diverse properties that may affect the acquisition of wh-questions: wh-in-situ (Malayalam and Mandarin); verb-final (German and Malayalam); case-marking on at least some wh-phrases (German, Hungarian, and Malayalam), word-order flexibility (German and Malayalam).
We found that (i) subject questions are easier for children than object questions--this was true also for languages without overt wh-movement; (ii) the question word "what" made questions easier, (iii) complex "which N" phrases are more difficult for children than simpler "who" and "what" questions to produce, and this was true across languages, and (iv) pronominal subjects make object questions easier than full NPs. Work is ongoing to extend our study to wider range of languages.