Matthew C. Galbraith ^*

• Pompeu Fabra University, Barcelona, Spain

Conversational user interfaces have transformed human-computer interaction by providing nearly real-time responses to queries. However, misunderstandings between the user and system persist. This study explores the significance of interactional language in dialogue repair between virtual assistants and users by analyzing interactions with Google Assistant and Siri in both English and Spanish, focusing on the assistants' utilization and response to the colloquial otherinitiated repair strategy "huh?", which is prevalent as a human-human dialogue repair strategy.Findings revealed ten distinct assistant-generated repair strategies, but an inability to replicate human-like strategies such as "huh?". Despite slight variations in user acceptability judgments among the two surveyed languages, results indicated an overall hierarchy of preference towards specific dialogue repair strategies, with a notable disparity between the most preferred strategies and those frequently used by the assistants. These findings highlight discrepancies in how interactional language is utilized in human-computer interaction, underscoring the need for further research on the impact of interactional elements among different languages to advance the development of conversational user interfaces across domains, including within human-robot interaction.