This paper reports an investigation of the interactions between groups of German and Danish speakers and a service robot which was programmed to produce English at an international university campus. We analysed three sets of interactions that involved an offer of water by the robot, and we used Conversation Analysis to track the human participants’ responses to the robot in examining how their language choice featured in their participation. We found that the overall organisation of the interactions was monolingual: participants used German and Danish with each other to express wonderment, frustration and confusion, and to comment on the robot’s actions, and English to respond to the robot’s offer and to ridicule it when acceptance of the offer was missed. Language choice and variations in volume when speaking each language, as added dimensions in recipient design, thus established monolingual participation frameworks. We argue that these findings reveal a different orientation to the robot as co-participant and question the extent to which robots are oriented to as social members in settings that mirror real-life contexts. Findings also raise design issues in the future development of robots.