A freeware, no-frills electronic tuning fork. All it does is allow the user to play a specific note. Useful for a cappella choirs when no-one has perfect pitch.是什么意思_A freeware, no-frills electronic tuning fork. All it does is allow the user to play a specific note. Useful for a cappella choirs when no-one has perfect pitch.在线翻译_英语_读音_用法_例句