Provided is a request rephrasing system 120 with which a conversation system can flexibly respond to various requests having different manners of expression, said request rephrasing system 120 comprising: a pre-processing unit 130 for converting a user input 56 into a word vector sequence; and a neural rephrasing model 94, pre-learned by machine learning, for receiving the word vector sequence as input and rephrasing the request represented by the word vector sequence as a request which a question/response device 122 has a higher probability of being able to respond to than before the rephrasing thereof. The system may involve determining whether the user input 56 is a request for the preprocessing and carrying out the rephrasing of the request only if the user input 56 is determined to be a request. In addition, the system may involve classifying which request classification the inputted request belongs to using a classification model 98 and inputting said classification into the neural rephrasing model 94 as one feature in the rephrasing.
REQUEST REPHRASING SYSTEM, METHOD FOR TRAINING OF REQUEST REPHRASING MODEL AND OF REQUEST DETERMINATION MODEL, AND CONVERSATION SYSTEM