Task: Question Answering
Input (English): We apply Han to such conversations in a sequential manner by feeding each user turn to Han as they occur, to determine if the conversation should escalate. If so, the user will be transferred to a live chat representative to continue the conversation. The user must wait for the human representative to review the IVA chat history and resume the failed task. 
 Question: How do they gather human reviews?
Output (English): human representative to review the IVA chat history and resume the failed task