To improve usability of a mobile telephone, when using the mobile telephone as a translation machine.

Text data are sent from the mobile telephone and received by a speech synthesis server 2. The text data are converted into speech data, which are sent to the mobile telephone 5. The speech data are received by the mobile telephone 5. Consequently, a translated sentence is outputted in voice, so that the usability during an overseas trip is superior. Further, since applications needed for translation and speech synthesis need not be installed in the mobile telephone 5, users can readily utilize it.