1：能够通过键盘演奏音符。 2：能够保存演奏的音乐，并实现回放。 3：有音调调整功能（如：C调，G调）。-1: notes can be played through the keyboard. 2: to be able to save the music played, and achieve playback. 3: tone adjustment function (such as: C tone, G notes).