D major
https://en.wikipedia.org/wiki/D_major
D major (or the key of D) is a major scale based on D, consisting of the pitches D, E, F♯, G, A, B, and C♯. Its key signature has two sharps. The D major scale is:
D, E, F♯, G, A, B, and C♯.--就是依照『全全半全全全半』的情況，所以出現 F♯ C♯ (請見阿原錄製的影片)
阿原短影片
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然後查到這篇，一下子，連小調的意思，阿原也懂了
