C Ionian, D Dorian, E Phrygian, F Lydian, G Micxolydian, A Aeolian and B Locrian all share the key signature of C Major so no sharps or flats found in any.

D Ionian, E Dorian, F# Phrygian, g Lydian, A Micxolydian, B Aeolian and C# Locrian all share the key signature of D Major, so the two sharps, F# and C# must always be honored among these.

etc.


--Mac