This article first presents an overview of some trends behind the acquisition of sociolinguistic variation in a second language. A study is then presented that aims to test the validity of these trends in a quantitative study of a range of socio- and morpho-phonetic variables in French, including liaison, /l/ deletion, and subject-verb agreement on irregular verbs in third-person-plural contexts. While such a comparative approach has been adopted in the case of Canadian immersion and naturalistic learners, the study presented here is concerned with Irish-instructed learners of French in the foreign language classroom. The study complements such previous work by further showing that the characteristics of the variables affect their differential acquisition by the instructed learner. The variables are discussed in relation to potential reasons for the similarities and differences in their acquisition.