Different languages adopt different grammatical options - SV, VS orders, (reduced) clefts - to answer the same question on the identification of the subject. The answering strategies are detected through speakers’ grammaticality judgements and through acquisition data, specially adult L2 acquisition. The direct relevance of acquisition data in raising and help clarifying theoretical issues is meant to be among the contributions of the article. The different answering strategies, analyzed in cartographic terms as involving either the VPperipheral internal focus position or focalization in situ, are all in principle available in different languages, provided that no formal condition is violated in the interaction with other properties, the crucial one being the null-subject vs non null-subject nature of the language. The different answering strategies are in place early on in first language monolingual acquisition. Speculative hypotheses on economy and the characterization of development, are put forth on the reason(s) why a strategy should prevail over the others, in compliance with formal conditions.