2. The method according to claim 1 , further comprising: calculating a confidence factor of each of the registration candidate words, wherein the confidence factor represents a degree of probability with which the registration candidate word is registered in the category dictionary or probability with which the registration candidate word is added to the token-sequence comparison rule.
2. The method according to claim 1 , further comprising: calculating a confidence factor of each of the registration candidate words, wherein the confidence factor represents a degree of probability with which the registration candidate word is registered in the category dictionary or probability with which the registration candidate word is added to the token-sequence comparison rule. 5. The method according to claim 2 , wherein permitting the user to select whether to register the registration candidate words comprises: sorting the registration candidate words according to the confidence factors calculated for each of the registration candidate words; and displaying the sorted registration candidate words on a display device.