Perfect voice training (Ontre) is "Pitatre 2" of each edition of "Textbook Perfect Training (Shinkoshuppansha Keirinkan)" (Keirinkan / Tokyo Shoseki / Sanseido / Mitsumura Tosho / Kairyudo / Kyoiku Shuppan) It is a voice training app that allows you to easily practice pronunciation of textbooks and Q & A that are compatible with the speaking app posted in.The users pronunciation is automatically graded using the pronunciation evaluation technology that utilizes the research results and voice information processing technology cultivated over many years at the Advanced Telecommunication Research Laboratories (ATR).