Authentic Cadence This is also known as a closed or standard cadence. It refers to the V chord to the I chord (or the IV - V - I). The dominant seventh (V7) can replace the dominant chord.
Dorian the tonic is D. The semitones are between the second and third and the sixth and seventh degrees.
Ionian the tonic is one. The semitones are between the third and fourth and the seventh and eighth degrees.
Lydian the tonic is four. The semitones are between the fourth and fifth and the seventh and eighth degrees.
Mixolydian the tonic is five. The semitones are between the third and fourth and the sixth and seventh degrees.
