This study investigates the second language (L2) acquisition of restrictive relative clauses (RRCs) in Chinese by two groups of learners speaking typologically different first languages (L1s): English and Korean. English RRCs, unlike those of Chinese, are head-initial whereas Korean RRCs, like those of Chinese, are head-final. The difference could be predicted to hinder English learners' acquisition of L2 RRCs but facilitate it for Korean learners. This prediction was not confirmed in this study, in fact the reverse was observed, and our data show contrasting patterns of acquisition between the two groups of learners. The English learners distinguished between target-like RRCs and non-target-like RRCs earlier than the Korean learners. A corresponding difference was observed for acquisition of resumptive pronouns. It is argued that where the L1 and the L2 share salient properties (such as head direction) restructuring of less salient features encoded in functional categories takes longer and may be persistently problematic. We suggest that the fact that Korean is more similar to Chinese (perhaps superficially, same head direction) leads learners not to restructure quickly, while the surface dissimilarity of English and Chinese gives rise to rapid restructuring in L2 grammars of learners. (Contains 7 tables and 5 footnotes.)