A method specifically includes, in a human-computer dialog interaction process, when a server performs slot extraction on user discourse, if there is a slot corresponding to which information fails to be extracted and the slot is an optional key slot, the server asks the user a question to determine whether the information corresponding to the slot is necessary. If the information is necessary, the server further extracts the information corresponding to the slot. If the information is unnecessary, the server does not extract the information corresponding to the slot.