textThe degree to which the two language systems of bilinguals are separate or interact in some way is a question that has been addressed using several methods. In the domain of morphosyntax, results from cross-linguistic priming have shown that bilinguals’ hearing a particular sentence structure in one of their languages increases the likelihood that they will produce a similar structure in the other language. This supports a shared-syntax model of bilingual processing in which bilinguals store similar structures together. Priming from L1 to L2 and L2 to L1 appears to be equally strong (Loebell & Bock, 2003; Schoonbaert, Hartsuiker, & Pickering, 2007) but researchers have not examined in depth how language experience and proficiency variab...