My guitar teacher - in my short student days - told me that each mode, in order to be expressed, have to be played over a certain chord.
That chord can either come from a second guitar, or from one guitar, if you play the chord right before you play the melody.
Ionian - Play Major or Major7
Dorian - Minor or Minor7
Phrygian - Minor or Minor7
Lydian - Major or Major7
Mixolydian - Dom7
Aeolian - Minor or Minor7
Lydian - Minor7b5
But then i watched this video:
But on 1:19, he says that If you play the major scale, your chord progression is this: C Major G Major A Minor F Major
Then on 1:50 he says that if you play the Mixolydian mode, these are the chords available to us:
C Major Bb Major F Major
So how do you know the chord available to you for each chord?
One more question, is this concept called 'Modal Harmonies'?