1. A voice guidance device comprising: a storing unit that stores a plurality of voice data items for each of a plurality of voice guidance phrases, wherein each of the plurality of voice data items for a specific voice guidance phrase includes the specific voice guidance phrase at a different frequency; a voice mixing unit that mixes at least two voice data items from a first voice guidance phrase of the plurality of guidance phrases to thereby produce a first mixed voice data item of the first voice guidance phrase; a voice outputting unit that outputs and sounds only the first voice guidance phrase using a first mixed voice based on the first mixed voice data item; a voice detecting unit that detects a response voice uttered by a user responding to the outputted first voice guidance phrase using the first mixed voice; and a voice measuring unit that measures a frequency with respect to the detected response voice; the voice mixing unit producing a second mixed voice data item by mixing at least two voice data items of a second voice guidance phrase from the plurality of voice guidance phrases, different than the first voice guidance phrase and different from the detected response, the second mixed voice data item having the characteristic of the frequency that is measured by the voice measuring unit with respect to the response voice detected after the first mixed voice was sounded; the voice outputting unit further outputting and sounding only the second voice guidance phrase using a second mixed voice based on the second mixed voice data item in response to the response voice, the second voice guidance phrase approximating the frequency that is measured by the voice measuring unit with respect to the response voice in order to assist the user to hear and understand the second voice guidance phrase.
1. A voice guidance device comprising: a storing unit that stores a plurality of voice data items for each of a plurality of voice guidance phrases, wherein each of the plurality of voice data items for a specific voice guidance phrase includes the specific voice guidance phrase at a different frequency; a voice mixing unit that mixes at least two voice data items from a first voice guidance phrase of the plurality of guidance phrases to thereby produce a first mixed voice data item of the first voice guidance phrase; a voice outputting unit that outputs and sounds only the first voice guidance phrase using a first mixed voice based on the first mixed voice data item; a voice detecting unit that detects a response voice uttered by a user responding to the outputted first voice guidance phrase using the first mixed voice; and a voice measuring unit that measures a frequency with respect to the detected response voice; the voice mixing unit producing a second mixed voice data item by mixing at least two voice data items of a second voice guidance phrase from the plurality of voice guidance phrases, different than the first voice guidance phrase and different from the detected response, the second mixed voice data item having the characteristic of the frequency that is measured by the voice measuring unit with respect to the response voice detected after the first mixed voice was sounded; the voice outputting unit further outputting and sounding only the second voice guidance phrase using a second mixed voice based on the second mixed voice data item in response to the response voice, the second voice guidance phrase approximating the frequency that is measured by the voice measuring unit with respect to the response voice in order to assist the user to hear and understand the second voice guidance phrase. 5. The voice guidance device of claim 1 , wherein the voice mixing unit produces the second mixed voice data item so that a voice volume of the second mixed voice increases as time elapses.