Yesterday Victoria asked me to teach her about the 7th chord of the 2nd scale degree in minor keys.
As I was going through all the different inversions, one of the prevailing questions was why this beautiful 4-note chord has so many resolutions?
You see, technically we only use resolutions which you can find in real music.
So, can you find a usage of this chord which resolves directly to tonic? Of course, this is very simple. But you have to double the third so that parallel fifths would be avoided (In A minor: BDFA-CCEA).
What about going from ii7 to the tonic through the 3-note dominant chord? Yes, and then you have to triple the root of the dominant and make this chord incomplete (BDFA-EEEG#-ACEA).
Can you resolve it to tonic through the 4-note chords (either inversions of D7 or vii7)? In the case of D7, two voices are moving by step and two are stationary (BDFA-BDEG#-ACEA). With vii7, only 1 voice is moving (BDFA-BDFG#-CCEA).
What if you wanted to make it a resolution through BOTH D7 and vii7? Then you simply move one note at a time (BDFA-BDFG#-BDEG#-ACEA).
You can also have the 5th resolution through altered 7th chord. Then you simply raise the 4th scale degree (BDFA-BD#FA-EEEG#-ACEA).
Does it seem complicated?
Sure it does. But the point is to resolve to tonic either directly or through the most common dissonant 3-note and 4-note chords.
After you understand it in theory, play it in practice in all major and minor keys. As always aim for at least 3 correct repetitions in a row.
Do you want to know if you're on the right path of your practice? Find an extra pair of ears/eyes that you trust and ask for feedback.
Hope this helps.