TAC Family Forums

Hiya @Roy-Phils

The chord of D Major (D, F#, A) is the 1-chord in the key of D-Major. However it’s also the 4-chord in the key of A-Major, and it’s the 5-chord in the key of G-Major.

1-4-5

G Major G-C-D

D Major D-G-A

A Major A-D-E

Hoping that helps with your question? And hope you are enjoying your music theory studies 🙂