Functional Categories and Acquisition Orders

We analyzed some earlier studies of English L1 and L2 morpheme orders, basing our analysis on current functional categories theory. Our analysis meets two long-standing charges against morpheme order data; namely, that the heterogeneity of the morphemes does not yield up any insights into L2 acquisition and that the English language-based orders lack generalizability. We suggest that the salient differences between the L1 and the L2 orders reduce to a number of simple contrasts. These involve (a) the category-specific emergence of functional categories in L1 versus their cross-category development in L2; (b) an L2 ordering hinging crucially on the lexical head versus inflectional head distinction in L2 and its absence in L1; (c) the at least coequal, or possibly even spearheading, role that inflections play vis-a-vis free functional categories in L1 versus the earlier and independent emergence of the latter in L2; and (d) the apparently greater difficulty that affix-movement poses for L2 learners.