ChatGPT as a Spanish teacher: the use of artificial intelligence tools to learn foreign language grammar

This paper considers the potential use of large language models as tools for foreign language learning, using their primary exponent, ChatGPT, as an example. From the perspective of a Spanish language student this tool has been presented with a series of questions regarding the use of the subjunctive mood in Spanish, starting with its simpler uses and building up to the more complex ones, in order to evaluate as much different uses, contexts and meanings as possible. The answers and explanations offered by the LLM were categorized with regard to accurateness and completeness, after which a qualitative and a quantitative analysis was undertaken. It was established that this language model offers adequate explanations in a limited number of cases, while, surprisingly, and in contrast with the initial hypotheses, ChatGPT failes to recognize as legitimate a significant number of completely correct Spanish structures. In addition, in some cases the model even goes on to generate grammatically unacceptable sequences.