In this study we explore the common ground between second-language writing and translated language as instances of constrained language use. Our research design involves three languages (English, Finnish, Italian), two constraining languages and two different registers in each of the three languages. These are compared in terms of frequency of syntactic structures (part-of-speech [POS] bigrams), adopting a corpus-driven method combining keyness analysis and multidimensional analysis. No general constrainedness effects that apply irrespective of languages and registers were observed, but our results point to the centrality of the opposition between verbal and nominal orientation for distinguishing constrained from unconstrained varieties. We conclude with suggestions on how our method and findings could lead to a deeper understanding of constrained language use, and be extended to different modes of language production and to language contact research in general.