Adverbial subordinate clauses in Spanish present significant complexities for learners of Spanish as a Foreign Language (SFL). This complexity is largely attributed to implicit grammatical rules, such as verbal agreement and the use of subjunctive forms, which pose challenges for learners. To explore this learning phenomenon more comprehensively, we investigated the acquisition of adverbial subordinate clauses through the lens of conceptual subordination, as proposed by Cristofaro (2003). Our study draws on existing research regarding language acquisition in populations with specific language impairments (SLI), particularly referencing Alvarado (2020). Leonard (2014) posits that children with SLI and second language learners may encounter similar difficulties due to the inherent characteristics of the linguistic systems they are acquiring. Consequently, we aimed to examine the extent to which the handling of adverbial subordinate clauses reveals parallels between the processes observed in children with SLI and those experienced by SFL students. To achieve this, we analyzed a sample of five intermediate-level ELE students who are native English speakers. Utilizing the PPCS framework (Alvarado, 2020), we elicited a corpus comprising 80 interclausal relations. Our analysis focused on two key aspects: (a) from a conceptual standpoint, we identified the asymmetrical relationships between two states of affairs (SoAs), and (b) from a formal perspective, we examined how these relationships were encoded-either through prototypical or alternative forms-while also considering the errors associated with each. The results revealed a substantial production of subordinating links, predominantly encoded using prototypical forms. However, there were notably more deviations in instances where alternative forms were utilized. While these findings do not entirely align with those observed in children with SLI, they provide valuable insights that support Leonard's hypotheses (2014) and contribute to a broader understanding of the acquisition process.