Nate Bosch teach us about the second mode of the major scale called ,,The Dorian Mode". On a C major scale he gonna play the notes found on that scale but starting from the second note of the scale called the second mode of the Dorian mode, playing all the notes starting from D. He end it off with another D. This is the Dorian mode of the C major scale: all the notes found on the C major scale played from the second note. The chord that can be built out of that scale is the 7th chord. Starting with the D, skipping note we playing F, skipping note we playing A, skipping note we play a C. That is a minor 7th chord, built of a Dorian mode of a scale in a key of C. The Dorian mode in the key of F, for example, would be all of the notes found in the F major scale but starting on the second note of every scale. This is how you build the 7th chord coming out of that note: start with the bottom note, G, skipping note, play the B flat, skipping note, play the D, skipping note, play the F. You've build the G minor 7th chord! And this is the Dorian mode!