A system and method to interactively converse with a cognitively overloaded user of a device, includes maintaining a knowledge base of information regarding the device and a domain, organizing the information in at least one of a relational manner and an ontological manner, receiving speech from the user, converting the speech into a word sequence, recognizing a partial proper name in the word sequence, identifying meaning structures from the word sequence using a model of the domain information, adjusting a boundary of the partial proper names to enhance an accuracy of the meaning structures, interpreting the meaning structures in a context of the conversation with the cognitively overloaded user using the knowledge base, selecting a content for a response to the cognitively overloaded user, generating the response based on the selected content, the context of the conversation, and grammatical rules, and synthesizing speech wave forms for the response.