hi guys . i am slowly getting music theory into my head, its been a challenge but well worth it. now i want to talk about modes and ask a question on the way.to make things easy ill base every thing on the C major scale. this scale has the following modes,C ionian,D dorian,Ephrigian,Flydian,Gmixolydian,A aeolian,Blocrian.now it is easy to see how these modes are created ,you just make each note a root and count forward. now if you harmonize all these modes in thirds you get the same chords just in a different order. all the notes again are the same just in a different order and it is this different order that changes the intervals of the modes. so which ever single note you play or chord you strum it is in the key of Cmajor. but when someone says that a song is written in Gmixolydian is it fair to say its written in C major as well?? if so why say its written in G mixolydian. now i think i know why you say G mixolydian and please correct me if i am wrong. lets say i strum the chords 1,5,1 of Cmajor C,G,C and then i do the same for GmixolydianG,Dm,G. what happens is that the two progressions sound different!so the first progression is written in C major and the second in Gmixolydian,right???i hope so. if i am right and i find myself analysing a chord progression that has all these chords C,G,Dm nothing else but these chords and no melody(notes) to help us analyse, how would i work out wether it is written in C major of Gmixolidian? PLEASE set me straight!!