METHODS AND MORPHEMES IN SECOND LANGUAGE ACQUISITION RESEARCH1

Recent morpheme studies of second language acquisition are methodologically difficult to interpret and the validity of some conclusions is questionable. The present study sought to ascertain (a) whether the morpheme order obtained using an elicitation instrument resembles the order of morphemes obtained from spontaneously collected second language acquisition speech data, and (b) whether the cross‐sectional and longitudinal research findings in second language acquisition research are comparable. The results of the study raise serious questions about the validity of cross‐sectional studies of second language acquisition based on instrument‐elicited morpheme data. The analysis of spontaneous data examined longitudinally suggests that such data may provide richer insights into the second language acquisition process.