PURPOSE: To monitor a memorized dial number by a subscriber in voice to confirm the dial number by providing a voice synthesizer synthesizing the voice corresponding to a dial number in the transmission operation of the subscriber by the specific number operation or the abbreviated dial.
CONSTITUTION: A voice synthesizer 4 synthesizing the voice corresponding to a dial number is provided. The content of a register 5 storing a dial transmitted from a calling subscriber 2 is decided as an access number of the abbreviated dial or a specific number requesting the confirmation of content of the abbreviated dial, then the dial information corresponding to the abbreviated dial is read from the storage memory, the voice synthesizer 4 is acquired and connected to the calling subscriber 2, and the telephone number corresponding to the abbreviated dial is transmitted to the calling subscriber by giving dial information to the voice synthesizer 4 and starting it.