so I read through a lot of the posts looking for my answer, but I couldn't find it. I learned about modes last night from my instructor. The way he taught them to me was to build them up, via the circle of 5ths. Ionian, then dorian, etc. I asked him when I would use these modes. He gave me an example of if the key of the song is C, and the chord at the moment is F, you could play a C Dorian and it would sound right on, since it would spell out the chord and the key at the same time. Actually, I don't remember what key and chord he said, I just kinda guessed there. But my question was, where else can modes be applied?